fix

* doc: update expired Slack invite link

* feat: add cloud mode to skill installer for team memory sharing

Adds support for Hindsight Cloud in the skill installer, enabling teams
to share memories about a codebase. Changes include:

- Add `--mode cloud` option to get-skill installer
- Install hindsight CLI binary for cloud mode (via get-cli)
- Configure ~/.hindsight/config with API URL and key
- Generate cloud-specific SKILL.md with team-aware guidance
- Distinguish between project conventions and individual preferences
- Update skills.md documentation with cloud setup instructions

Cloud mode workflow:
1. Team admin creates a bank in Hindsight Cloud
2. Each developer runs: curl ... | bash -s -- --mode cloud
3. All team members share the same memory bank
4. Knowledge retained by one member benefits everyone

.env.example

@@ -2,11 +2,23 @@
 # Copy this file to .env and fill in your values
 
 # LLM Configuration (Required)
+# Supported providers: openai, groq, ollama, gemini, anthropic, lmstudio
 HINDSIGHT_API_LLM_PROVIDER=openai
 HINDSIGHT_API_LLM_API_KEY=your-api-key-here
 HINDSIGHT_API_LLM_MODEL=o3-mini
 HINDSIGHT_API_LLM_BASE_URL=https://api.openai.com/v1
 
+# Example: Anthropic Claude configuration
+# HINDSIGHT_API_LLM_PROVIDER=anthropic
+# HINDSIGHT_API_LLM_API_KEY=your-anthropic-api-key
+# HINDSIGHT_API_LLM_MODEL=claude-sonnet-4-20250514
+
+# Example: LM Studio local configuration (Qwen 2.5 32B recommended)
+# HINDSIGHT_API_LLM_PROVIDER=lmstudio
+# HINDSIGHT_API_LLM_API_KEY=lmstudio
+# HINDSIGHT_API_LLM_BASE_URL=http://localhost:1234/v1
+# HINDSIGHT_API_LLM_MODEL=qwen2.5-32b-instruct
+
 # API Configuration (Optional)
 HINDSIGHT_API_HOST=0.0.0.0
 HINDSIGHT_API_PORT=8888

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -0,0 +1,71 @@
+name: Bug Report
+description: Report a bug or unexpected behavior
+labels: ["bug", "triage"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for taking the time to report a bug! Please fill out the sections below.
+
+  - type: textarea
+    id: description
+    attributes:
+      label: Bug Description
+      description: A clear and concise description of the bug
+      placeholder: What happened?
+    validations:
+      required: true
+
+  - type: textarea
+    id: reproduction
+    attributes:
+      label: Steps to Reproduce
+      description: Steps to reproduce the behavior
+      placeholder: |
+        1. Configure '...'
+        2. Call '...'
+        3. See error
+    validations:
+      required: true
+
+  - type: textarea
+    id: expected
+    attributes:
+      label: Expected Behavior
+      description: What did you expect to happen?
+    validations:
+      required: true
+
+  - type: textarea
+    id: actual
+    attributes:
+      label: Actual Behavior
+      description: What actually happened?
+    validations:
+      required: true
+
+  - type: input
+    id: version
+    attributes:
+      label: Version
+      description: What version are you using?
+      placeholder: e.g., 0.1.0 or commit hash
+    validations:
+      required: false
+
+  - type: dropdown
+    id: llm-provider
+    attributes:
+      label: LLM Provider
+      description: Which LLM provider are you using?
+      options:
+        - OpenAI
+        - Anthropic
+        - Gemini
+        - Groq
+        - Ollama
+        - LM Studio
+        - Other
+    validations:
+      required: false
+

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,8 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Questions & Help
+    url: https://github.com/vectorize-io/hindsight/discussions/categories/q-a
+    about: Please ask questions and get help in Discussions instead of opening an issue.
+  - name: Ideas & Feedback
+    url: https://github.com/vectorize-io/hindsight/discussions/categories/ideas
+    about: Share ideas or give feedback in Discussions.

.github/ISSUE_TEMPLATE/feature_request.yml

@@ -0,0 +1,82 @@
+name: Feature Request
+description: Suggest a new feature or enhancement
+labels: ["enhancement", "triage"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for suggesting a feature! Please describe what you'd like to see added.
+
+  - type: textarea
+    id: use-case
+    attributes:
+      label: Use Case
+      description: Describe your specific use case. What are you building? What's your goal?
+      placeholder: |
+        I'm building an AI agent that needs to...
+        My application handles...
+    validations:
+      required: true
+
+  - type: textarea
+    id: problem
+    attributes:
+      label: Problem Statement
+      description: What problem are you facing? What's missing or difficult today?
+      placeholder: Currently I have to... which causes...
+    validations:
+      required: true
+
+  - type: textarea
+    id: benefit
+    attributes:
+      label: How This Feature Would Help
+      description: Explain how this feature would improve your workflow or solve your problem
+      placeholder: With this feature, I would be able to...
+    validations:
+      required: true
+
+  - type: textarea
+    id: solution
+    attributes:
+      label: Proposed Solution
+      description: Describe your ideal solution (optional - we may have ideas too!)
+      placeholder: It would be great if Hindsight could...
+    validations:
+      required: false
+
+  - type: textarea
+    id: alternatives
+    attributes:
+      label: Alternatives Considered
+      description: Have you considered any alternative solutions or workarounds?
+    validations:
+      required: false
+
+  - type: dropdown
+    id: priority
+    attributes:
+      label: Priority
+      description: How important is this feature to you?
+      options:
+        - Nice to have
+        - Important - affects my workflow
+        - Critical - blocking my use case
+    validations:
+      required: true
+
+  - type: textarea
+    id: additional
+    attributes:
+      label: Additional Context
+      description: Any other context, mockups, or examples?
+    validations:
+      required: false
+
+  - type: checkboxes
+    id: checklist
+    attributes:
+      label: Checklist
+      options:
+        - label: I would be willing to contribute this feature
+          required: false

.github/workflows/release.yml

@@ -42,6 +42,10 @@ jobs:
       working-directory: ./hindsight-integrations/litellm
       run: uv build --out-dir dist
 
+    - name: Build hindsight-embed
+      working-directory: ./hindsight-embed
+      run: uv build --out-dir dist
+
     # Publish in order (client and api first, then hindsight-all which depends on them)
     - name: Publish hindsight-client to PyPI
       uses: pypa/gh-action-pypi-publish@release/v1
@@ -67,6 +71,12 @@ jobs:
         packages-dir: ./hindsight-integrations/litellm/dist
         skip-existing: true
 
+    - name: Publish hindsight-embed to PyPI
+      uses: pypa/gh-action-pypi-publish@release/v1
+      with:
+        packages-dir: ./hindsight-embed/dist
+        skip-existing: true
+
     # Upload artifacts for GitHub release
     - name: Upload artifacts
       uses: actions/upload-artifact@v4
@@ -77,6 +87,7 @@ jobs:
           hindsight-api/dist/*
           hindsight/dist/*
           hindsight-integrations/litellm/dist/*
+          hindsight-embed/dist/*
         retention-days: 1
 
   release-typescript-client:
@@ -416,6 +427,7 @@ jobs:
         cp artifacts/python-packages/hindsight-api/dist/* release-assets/ || true
         cp artifacts/python-packages/hindsight/dist/* release-assets/ || true
         cp artifacts/python-packages/hindsight-integrations/litellm/dist/* release-assets/ || true
+        cp artifacts/python-packages/hindsight-embed/dist/* release-assets/ || true
         # TypeScript client
         cp artifacts/typescript-client/*.tgz release-assets/ || true
         # Control Plane

.github/workflows/test.yml

@@ -20,6 +20,8 @@ jobs:
             path: hindsight-api
           - name: hindsight-client
             path: hindsight-clients/python
+          - name: hindsight-embed
+            path: hindsight-embed
 
     steps:
     - uses: actions/checkout@v4
@@ -180,6 +182,83 @@ jobs:
         path: hindsight-cli/target/release/hindsight
         retention-days: 1
 
+  test-rust-cli:
+    runs-on: ubuntu-latest
+    needs: build-rust-cli
+    env:
+      HINDSIGHT_API_LLM_PROVIDER: groq
+      HINDSIGHT_API_LLM_API_KEY: ${{ secrets.GROQ_API_KEY }}
+      HINDSIGHT_API_LLM_MODEL: openai/gpt-oss-20b
+      HINDSIGHT_API_URL: http://localhost:8888
+      GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      UV_INDEX: pytorch=https://download.pytorch.org/whl/cpu
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Download CLI artifact
+      uses: actions/download-artifact@v4
+      with:
+        name: hindsight-cli
+        path: /tmp/cli
+
+    - name: Make CLI executable
+      run: chmod +x /tmp/cli/hindsight
+
+    - name: Install uv
+      uses: astral-sh/setup-uv@v5
+      with:
+        enable-cache: true
+        prune-cache: false
+
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version-file: ".python-version"
+
+    - name: Build API
+      working-directory: ./hindsight-api
+      run: uv build
+
+    - name: Install API dependencies
+      working-directory: ./hindsight-api
+      run: uv sync --frozen --no-install-project --index-strategy unsafe-best-match
+
+    - name: Create .env file
+      run: |
+        cat > .env << EOF
+        HINDSIGHT_API_LLM_PROVIDER=${{ env.HINDSIGHT_API_LLM_PROVIDER }}
+        HINDSIGHT_API_LLM_API_KEY=${{ env.HINDSIGHT_API_LLM_API_KEY }}
+        HINDSIGHT_API_LLM_MODEL=${{ env.HINDSIGHT_API_LLM_MODEL }}
+        EOF
+
+    - name: Start API server
+      run: |
+        ./scripts/dev/start-api.sh > /tmp/api-server.log 2>&1 &
+        echo "Waiting for API server to be ready..."
+        for i in {1..60}; do
+          if curl -sf http://localhost:8888/health > /dev/null 2>&1; then
+            echo "API server is ready after ${i}s"
+            break
+          fi
+          if [ $i -eq 60 ]; then
+            echo "API server failed to start after 60s"
+            cat /tmp/api-server.log
+            exit 1
+          fi
+          sleep 1
+        done
+
+    - name: Run CLI smoke test
+      run: |
+        HINDSIGHT_CLI=/tmp/cli/hindsight ./hindsight-cli/smoke-test.sh
+
+    - name: Show API server logs
+      if: always()
+      run: |
+        echo "=== API Server Logs ==="
+        cat /tmp/api-server.log || echo "No API server log found"
+
   lint-helm-chart:
     runs-on: ubuntu-latest
 
@@ -246,6 +325,8 @@ jobs:
       GROQ_API_KEY: ${{ secrets.GROQ_API_KEY }}
       GEMINI_API_KEY: ${{ secrets.GEMINI_API_KEY }}
       OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
+      COHERE_API_KEY: ${{ secrets.COHERE_API_KEY }}
+      HINDSIGHT_API_EMBEDDINGS_OPENAI_API_KEY: ${{ secrets.OPENAI_API_KEY }}
       HINDSIGHT_API_LLM_MODEL: openai/gpt-oss-20b
       GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       # Prefer CPU-only PyTorch in CI (but keep PyPI for everything else)
@@ -271,7 +352,7 @@ jobs:
 
     - name: Install dependencies
       working-directory: ./hindsight-api
-      run: uv sync --extra test --no-install-project --index-strategy unsafe-best-match
+      run: uv sync --frozen --extra test --no-install-project --index-strategy unsafe-best-match
 
     - name: Cache HuggingFace models
       uses: actions/cache@v4
@@ -332,11 +413,11 @@ jobs:
 
     - name: Install client test dependencies
       working-directory: ./hindsight-clients/python
-      run: uv sync --extra test --index-strategy unsafe-best-match
+      run: uv sync --frozen --extra test --index-strategy unsafe-best-match
 
     - name: Install API dependencies
       working-directory: ./hindsight-api
-      run: uv sync --no-install-project --index-strategy unsafe-best-match
+      run: uv sync --frozen --no-install-project --index-strategy unsafe-best-match
 
     - name: Create .env file
       run: |
@@ -409,7 +490,7 @@ jobs:
 
     - name: Install API dependencies
       working-directory: ./hindsight-api
-      run: uv sync --no-install-project --index-strategy unsafe-best-match
+      run: uv sync --frozen --no-install-project --index-strategy unsafe-best-match
 
     - name: Install TypeScript client dependencies
       working-directory: ./hindsight-clients/typescript
@@ -497,7 +578,7 @@ jobs:
 
     - name: Install API dependencies
       working-directory: ./hindsight-api
-      run: uv sync --no-install-project --index-strategy unsafe-best-match
+      run: uv sync --frozen --no-install-project --index-strategy unsafe-best-match
 
     - name: Create .env file
       run: |
@@ -534,6 +615,97 @@ jobs:
         echo "=== API Server Logs ==="
         cat /tmp/api-server.log || echo "No API server log found"
 
+  test-integration:
+    runs-on: ubuntu-latest
+    env:
+      HINDSIGHT_API_LLM_PROVIDER: groq
+      HINDSIGHT_API_LLM_API_KEY: ${{ secrets.GROQ_API_KEY }}
+      HINDSIGHT_API_LLM_MODEL: openai/gpt-oss-20b
+      HINDSIGHT_API_URL: http://localhost:8888
+      GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+      UV_INDEX: pytorch=https://download.pytorch.org/whl/cpu
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Install uv
+      uses: astral-sh/setup-uv@v5
+      with:
+        enable-cache: true
+        prune-cache: false
+
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version-file: ".python-version"
+
+    - name: Build API
+      working-directory: ./hindsight-api
+      run: uv build
+
+    - name: Install API dependencies
+      working-directory: ./hindsight-api
+      run: uv sync --frozen --no-install-project --index-strategy unsafe-best-match
+
+    - name: Install integration test dependencies
+      working-directory: ./hindsight-integration-tests
+      run: uv sync --frozen
+
+    - name: Cache HuggingFace models
+      uses: actions/cache@v4
+      with:
+        path: ~/.cache/huggingface
+        key: ${{ runner.os }}-huggingface-${{ hashFiles('hindsight-api/pyproject.toml') }}
+        restore-keys: |
+          ${{ runner.os }}-huggingface-
+
+    - name: Pre-download models
+      working-directory: ./hindsight-api
+      run: |
+        uv run python -c "
+        from sentence_transformers import SentenceTransformer, CrossEncoder
+        print('Downloading embedding model...')
+        SentenceTransformer('BAAI/bge-small-en-v1.5')
+        print('Downloading cross-encoder model...')
+        CrossEncoder('cross-encoder/ms-marco-MiniLM-L-6-v2')
+        print('Models downloaded successfully')
+        "
+
+    - name: Create .env file
+      run: |
+        cat > .env << EOF
+        HINDSIGHT_API_LLM_PROVIDER=${{ env.HINDSIGHT_API_LLM_PROVIDER }}
+        HINDSIGHT_API_LLM_API_KEY=${{ env.HINDSIGHT_API_LLM_API_KEY }}
+        HINDSIGHT_API_LLM_MODEL=${{ env.HINDSIGHT_API_LLM_MODEL }}
+        EOF
+
+    - name: Start API server
+      run: |
+        ./scripts/dev/start-api.sh > /tmp/api-server.log 2>&1 &
+        echo "Waiting for API server to be ready..."
+        for i in {1..60}; do
+          if curl -sf http://localhost:8888/health > /dev/null 2>&1; then
+            echo "API server is ready after ${i}s"
+            break
+          fi
+          if [ $i -eq 60 ]; then
+            echo "API server failed to start after 60s"
+            cat /tmp/api-server.log
+            exit 1
+          fi
+          sleep 1
+        done
+
+    - name: Run integration tests
+      working-directory: ./hindsight-integration-tests
+      run: uv run pytest tests/ -v
+
+    - name: Show API server logs
+      if: always()
+      run: |
+        echo "=== API Server Logs ==="
+        cat /tmp/api-server.log || echo "No API server log found"
+
   test-litellm-integration:
     runs-on: ubuntu-latest
 
@@ -557,12 +729,52 @@ jobs:
 
     - name: Install dependencies
       working-directory: ./hindsight-integrations/litellm
-      run: uv sync --extra dev
+      run: uv sync --frozen --extra dev
 
     - name: Run tests
       working-directory: ./hindsight-integrations/litellm
       run: uv run pytest tests -v
 
+  test-embed:
+    runs-on: ubuntu-latest
+    env:
+      HINDSIGHT_EMBED_LLM_PROVIDER: groq
+      HINDSIGHT_EMBED_LLM_API_KEY: ${{ secrets.GROQ_API_KEY }}
+      HINDSIGHT_EMBED_LLM_MODEL: openai/gpt-oss-20b
+      # Prefer CPU-only PyTorch in CI
+      UV_INDEX: pytorch=https://download.pytorch.org/whl/cpu
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Install uv
+      uses: astral-sh/setup-uv@v5
+      with:
+        enable-cache: true
+        prune-cache: false
+
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version-file: ".python-version"
+
+    - name: Install dependencies
+      working-directory: ./hindsight-embed
+      run: uv sync --frozen --index-strategy unsafe-best-match
+
+    - name: Cache HuggingFace models
+      uses: actions/cache@v4
+      with:
+        path: ~/.cache/huggingface
+        key: ${{ runner.os }}-huggingface-embed-${{ hashFiles('hindsight-embed/pyproject.toml') }}
+        restore-keys: |
+          ${{ runner.os }}-huggingface-embed-
+          ${{ runner.os }}-huggingface-
+
+    - name: Run smoke test
+      working-directory: ./hindsight-embed
+      run: ./test.sh
+
   test-doc-examples:
     runs-on: ubuntu-latest
     needs: build-rust-cli
@@ -608,11 +820,11 @@ jobs:
       working-directory: ./hindsight-api
       run: |
         uv build
-        uv sync --no-install-project --index-strategy unsafe-best-match
+        uv sync --frozen --no-install-project --index-strategy unsafe-best-match
 
     - name: Install Python client dependencies
       working-directory: ./hindsight-clients/python
-      run: uv sync --extra test --index-strategy unsafe-best-match
+      run: uv sync --frozen --extra test --index-strategy unsafe-best-match
 
     - name: Install TypeScript client
       run: |
@@ -673,4 +885,76 @@ jobs:
       if: always()
       run: |
         echo "=== API Server Logs ==="
-        cat /tmp/api-server.log || echo "No API server log found"
+        cat /tmp/api-server.log || echo "No API server log found"
+
+  verify-generated-files:
+    runs-on: ubuntu-latest
+    env:
+      UV_INDEX: pytorch=https://download.pytorch.org/whl/cpu
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Install uv
+      uses: astral-sh/setup-uv@v5
+      with:
+        enable-cache: true
+
+    - name: Set up Python
+      uses: actions/setup-python@v5
+      with:
+        python-version-file: ".python-version"
+
+    - name: Set up Node.js
+      uses: actions/setup-node@v4
+      with:
+        node-version: '20'
+        cache: 'npm'
+        cache-dependency-path: package-lock.json
+
+    - name: Install Rust
+      uses: dtolnay/rust-toolchain@stable
+
+    - name: Cache cargo
+      uses: actions/cache@v4
+      with:
+        path: |
+          ~/.cargo/registry
+          ~/.cargo/git
+        key: ${{ runner.os }}-cargo-gen-${{ hashFiles('**/Cargo.lock') }}
+
+    - name: Install Node dependencies
+      run: npm ci
+
+    - name: Install Python dependencies
+      run: |
+        cd hindsight-dev && uv sync --frozen --index-strategy unsafe-best-match
+        cd ../hindsight-api && uv sync --frozen --index-strategy unsafe-best-match
+        cd ../hindsight-embed && uv sync --frozen --index-strategy unsafe-best-match
+
+    - name: Run generate-openapi
+      run: ./scripts/generate-openapi.sh
+
+    - name: Run generate-clients
+      run: ./scripts/generate-clients.sh
+
+    - name: Run lint
+      run: ./scripts/hooks/lint.sh
+
+    - name: Verify no uncommitted changes
+      run: |
+        if [ -n "$(git status --porcelain)" ]; then
+          echo "❌ Error: Generated files are out of sync with committed files."
+          echo ""
+          echo "The following files have changed after running generation scripts:"
+          git status --porcelain
+          echo ""
+          echo "Please run the following commands locally and commit the changes:"
+          echo "  ./scripts/generate-openapi.sh"
+          echo "  ./scripts/generate-clients.sh"
+          echo "  ./scripts/hooks/lint.sh"
+          echo ""
+          git diff --stat
+          exit 1
+        fi
+        echo "✓ All generated files are up to date"

.gitignore

@@ -5,15 +5,18 @@ build/
 dist/
 wheels/
 *.egg-info
-
+.mcp.json
+.osgrep
 # Virtual environments
 .venv
 
 # Node
 node_modules/
 
-# Environment variables
+# Environment variables and local config
 .env
+docker-compose.yml
+docker-compose.override.yml
 
 # IDE
 .idea/
@@ -24,6 +27,10 @@ node_modules/
 # NLTK data (will be downloaded automatically)
 nltk_data/
 
+# Monitoring stack (Prometheus/Grafana binaries and data)
+.monitoring/
+.pgbouncer
+
 # Large benchmark datasets (will be downloaded automatically)
 **/longmemeval_s_cleaned.json
 
@@ -39,4 +46,8 @@ hindsight-docs/static/llms-full.txt
 hindsight-dev/benchmarks/locomo/results/
 hindsight-dev/benchmarks/longmemeval/results/
 hindsight-cli/target
-hindsight-clients/rust/target
+hindsight-clients/rust/target
+.claude
+whats-next.md
+TASK.md
+CHANGELOG.md

.pgbouncer/pgbouncer.ini

@@ -0,0 +1,39 @@
+[databases]
+; Connect to pg0 on port 5433
+; The actual pg0 database is called "hindsight"
+hindsight = host=127.0.0.1 port=5433 dbname=hindsight user=hindsight password=hindsight
+
+[pgbouncer]
+listen_addr = 127.0.0.1
+listen_port = 6432
+
+; Use md5 authentication (matches pg0's auth)
+auth_type = md5
+auth_file = /Users/nicoloboschi/dev/memory-poc/.pgbouncer/userlist.txt
+
+; Transaction pooling mode (recommended for hindsight)
+pool_mode = transaction
+
+; Reset connection state after each transaction
+server_reset_query = DISCARD ALL
+
+; Pool sizing
+default_pool_size = 20
+max_client_conn = 200
+min_pool_size = 5
+
+; Timeouts
+server_idle_timeout = 600
+server_lifetime = 3600
+query_timeout = 120
+
+; Logging
+log_connections = 1
+log_disconnections = 1
+log_pooler_errors = 1
+
+; Stats
+stats_period = 60
+
+; Admin console
+admin_users = admin

.pgbouncer/userlist.txt

@@ -0,0 +1,2 @@
+"hindsight" "md5d842ccb6249bcd3c53b2f648378092a6"
+"admin" ""

AGENTS.md

@@ -14,6 +14,7 @@ This document captures architectural decisions and coding conventions for the Hi
 hindsight/              # Python package for embedded usage
 hindsight-api/          # FastAPI server (core memory engine)
 hindsight-cli/          # Rust CLI client
+hindsight-embed/        # Embedded CLI (no server needed)
 hindsight-control-plane/ # Next.js admin UI
 hindsight-docs/         # Docusaurus documentation site
 hindsight-dev/          # Development tools and benchmarks
@@ -148,4 +149,5 @@ Note: The maintained wrapper `hindsight_client.py` and `README.md` are preserved
 
 # Branding
 ## Colors
-- Primary: gradient from #0074d9 to #009296  
+- Primary: gradient from #0074d9 to #009296
+

CLAUDE.md

@@ -0,0 +1,251 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+Hindsight is an agent memory system that provides long-term memory for AI agents using biomimetic data structures. Memories are organized as:
+- **World facts**: General knowledge ("The sky is blue")
+- **Experience facts**: Personal experiences ("I visited Paris in 2023")
+- **Opinion facts**: Beliefs with confidence scores ("Paris is beautiful" - 0.9 confidence)
+- **Observations**: Complex mental models derived from reflection
+
+## Development Commands
+
+### API Server (Python/FastAPI)
+```bash
+# Start API server (loads .env automatically)
+./scripts/dev/start-api.sh
+
+# Run all tests (parallelized with pytest-xdist)
+cd hindsight-api && uv run pytest tests/
+
+# Run specific test file
+cd hindsight-api && uv run pytest tests/test_http_api_integration.py -v
+
+# Run single test function
+cd hindsight-api && uv run pytest tests/test_retain.py::test_retain_simple -v
+
+# Lint and format
+cd hindsight-api && uv run ruff check .
+cd hindsight-api && uv run ruff format .
+
+# Type checking (uses ty - extremely fast type checker from Astral)
+cd hindsight-api && uv run ty check hindsight_api/
+```
+
+### Control Plane (Next.js)
+```bash
+./scripts/dev/start-control-plane.sh
+# Or manually:
+cd hindsight-control-plane && npm run dev
+```
+
+### Documentation Site (Docusaurus)
+```bash
+./scripts/dev/start-docs.sh
+```
+
+### Generating Clients/OpenAPI
+```bash
+# Regenerate OpenAPI spec after API changes (REQUIRED after changing endpoints)
+./scripts/generate-openapi.sh
+
+# Regenerate all client SDKs (Python, TypeScript, Rust)
+./scripts/generate-clients.sh
+```
+
+### Benchmarks
+```bash
+./scripts/benchmarks/run-longmemeval.sh
+./scripts/benchmarks/run-locomo.sh
+./scripts/benchmarks/start-visualizer.sh  # View results at localhost:8001
+```
+
+## Architecture
+
+### Monorepo Structure
+- **hindsight-api/**: Core FastAPI server with memory engine (Python, uv)
+- **hindsight/**: Embedded Python bundle (hindsight-all package)
+- **hindsight-control-plane/**: Admin UI (Next.js, npm)
+- **hindsight-cli/**: CLI tool (Rust, cargo, uses progenitor for API client)
+- **hindsight-clients/**: Generated SDK clients (Python, TypeScript, Rust)
+- **hindsight-docs/**: Docusaurus documentation site
+- **hindsight-integrations/**: Framework integrations (LiteLLM, OpenAI)
+- **hindsight-dev/**: Development tools and benchmarks
+
+### Core Engine (hindsight-api/hindsight_api/engine/)
+- `memory_engine.py`: Main orchestrator (~170KB) for retain/recall/reflect operations
+- `llm_wrapper.py`: LLM abstraction supporting OpenAI, Anthropic, Gemini, Groq, Ollama, LM Studio
+- `embeddings.py`: Embedding generation (local sentence-transformers or TEI)
+- `cross_encoder.py`: Reranking (local or TEI)
+- `entity_resolver.py`: Entity extraction and normalization
+- `query_analyzer.py`: Query intent analysis
+
+**retain/**: Memory ingestion pipeline
+- `orchestrator.py`: Coordinates the retain flow
+- `fact_extraction.py`: LLM-based fact extraction from content
+- `link_utils.py`: Entity link creation and management
+
+**search/**: Multi-strategy retrieval
+- `retrieval.py`: Main retrieval orchestrator
+- `graph_retrieval.py`: Entity/relationship graph traversal
+- `mpfp_retrieval.py`: Multi-Path Fact Propagation retrieval
+- `fusion.py`: Reciprocal rank fusion for combining results
+- `reranking.py`: Cross-encoder reranking
+
+### API Layer (hindsight-api/hindsight_api/api/)
+- `http.py`: FastAPI HTTP routers (~80KB) for all REST endpoints
+- `mcp.py`: Model Context Protocol server implementation
+
+Main operations:
+- **Retain**: Store memories, extracts facts/entities/relationships
+- **Recall**: Retrieve memories via 4 parallel strategies (semantic, BM25, graph, temporal) + reranking
+- **Reflect**: Deep analysis forming new opinions/observations (disposition-aware)
+
+### Database
+PostgreSQL with pgvector. Schema managed via Alembic migrations in `hindsight-api/hindsight_api/alembic/`. Migrations run automatically on API startup.
+
+Key tables: `banks`, `memory_units`, `documents`, `entities`, `entity_links`
+
+### Adding Database Migrations
+
+1. **Create a new migration file** in `hindsight-api/hindsight_api/alembic/versions/`:
+   - File name format: `<revision_id>_<description>.py` (e.g., `f1a2b3c4d5e6_add_new_index.py`)
+   - Use a unique hex revision ID (12 chars)
+   - Set `down_revision` to the previous migration's revision ID
+
+2. **Migration template**:
+   ```python
+   """Description of the migration
+
+   Revision ID: f1a2b3c4d5e6
+   Revises: <previous_revision_id>
+   Create Date: YYYY-MM-DD
+   """
+   from collections.abc import Sequence
+   from alembic import context, op
+
+   revision: str = "f1a2b3c4d5e6"
+   down_revision: str | Sequence[str] | None = "<previous_revision_id>"
+   branch_labels: str | Sequence[str] | None = None
+   depends_on: str | Sequence[str] | None = None
+
+   def _get_schema_prefix() -> str:
+       """Get schema prefix for table names (required for multi-tenant support)."""
+       schema = context.config.get_main_option("target_schema")
+       return f'"{schema}".' if schema else ""
+
+   def upgrade() -> None:
+       schema = _get_schema_prefix()
+       op.execute(f"CREATE INDEX ... ON {schema}table_name(...)")
+
+   def downgrade() -> None:
+       schema = _get_schema_prefix()
+       op.execute(f"DROP INDEX IF EXISTS {schema}index_name")
+   ```
+
+3. **Run migrations locally**:
+   ```bash
+   # Set database URL and run migrations
+   uv run hindsight-admin run-db-migration
+
+   # Run on a specific tenant schema
+   uv run hindsight-admin run-db-migration --schema tenant_xyz
+   ```
+
+## Key Conventions
+
+### Code Quality
+**Always run the lint script after making Python or TypeScript/Node changes:**
+```bash
+./scripts/hooks/lint.sh
+```
+This runs the same checks as the pre-commit hook (Ruff for Python, ESLint/Prettier for TypeScript).
+
+### Memory Banks
+- Each bank is an isolated memory store (like a "brain" for one user/agent)
+- Banks have dispositions (skepticism, literalism, empathy traits 1-5) affecting reflect
+- Banks can have background context
+- Bank isolation is strict - no cross-bank data leakage
+
+### API Design
+- All endpoints operate on a single bank per request
+- Multi-bank queries are client responsibility to orchestrate
+- Disposition traits only affect reflect, not recall
+
+### Control Plane API Routes
+
+When adding or modifying parameters in the dataplane API (hindsight-api), you must also update the control plane routes that proxy to it:
+
+1. **API Routes** (`hindsight-control-plane/src/app/api/`):
+   - `recall/route.ts` - proxies to `/v1/default/banks/{bank_id}/memories/recall`
+   - `reflect/route.ts` - proxies to `/v1/default/banks/{bank_id}/reflect`
+   - `memories/retain/route.ts` - proxies to `/v1/default/banks/{bank_id}/memories/retain`
+   - Other routes follow the same pattern
+
+2. **Client types** (`hindsight-control-plane/src/lib/api.ts`):
+   - Update the TypeScript type definitions for `recall()`, `reflect()`, `retain()` etc.
+
+3. **Checklist when adding new API parameters**:
+   - Add parameter extraction in the route handler (destructure from `body`)
+   - Pass the parameter to the SDK call
+   - Update the client type definition in `lib/api.ts`
+   - Update any UI components that need to use the new parameter
+
+### Python Style
+- Python 3.11+, type hints required
+- Async throughout (asyncpg, async FastAPI)
+- Pydantic models for request/response
+- Ruff for linting (line-length 120)
+- No Python files at project root - maintain clean directory structure
+
+### TypeScript Style
+- Next.js App Router for control plane
+- Tailwind CSS with shadcn/ui components
+
+### Adding New API Configuration Flags
+
+When adding a new environment variable configuration:
+
+1. **config.py** (`hindsight-api/hindsight_api/config.py`):
+   - Add `ENV_*` constant for the environment variable name
+   - Add `DEFAULT_*` constant for the default value
+   - Add field to `HindsightConfig` dataclass
+   - Add initialization in `from_env()` method
+
+2. **main.py** (`hindsight-api/hindsight_api/main.py`):
+   - Add field to the manual `HindsightConfig()` constructor call (search for "CLI override")
+
+3. **Use the config** in code:
+   ```python
+   from ...config import get_config
+   config = get_config()
+   value = config.your_new_field
+   ```
+
+4. **Documentation** (`hindsight-docs/docs/developer/configuration.md`):
+   - Add to appropriate section table with Variable, Description, Default
+
+## Environment Setup
+
+```bash
+cp .env.example .env
+# Edit .env with LLM API key
+
+# Python deps
+uv sync --directory hindsight-api/
+
+# Node deps (uses npm workspaces)
+npm install
+```
+
+Required env vars:
+- `HINDSIGHT_API_LLM_PROVIDER`: openai, anthropic, gemini, groq, ollama, lmstudio
+- `HINDSIGHT_API_LLM_API_KEY`: Your API key
+- `HINDSIGHT_API_LLM_MODEL`: Model name (e.g., o3-mini, claude-sonnet-4-20250514)
+
+Optional (uses local models by default):
+- `HINDSIGHT_API_EMBEDDINGS_PROVIDER`: local (default) or tei
+- `HINDSIGHT_API_RERANKER_PROVIDER`: local (default) or tei
+- `HINDSIGHT_API_DATABASE_URL`: External PostgreSQL (uses embedded pg0 by default)

CONTRIBUTING.md

@@ -51,7 +51,36 @@ cd hindsight-api
 uv run pytest tests/
 ```
 
-### Code style
+### Code Style
+
+We use [Ruff](https://docs.astral.sh/ruff/) for Python linting and formatting, and ESLint/Prettier for TypeScript.
+
+#### Setting up git hooks (recommended)
+
+Set up git hooks to automatically lint and format code before each commit:
+
+```bash
+./scripts/setup-hooks.sh
+```
+
+This configures git to use the hooks in `.githooks/`, which run all scripts in `scripts/hooks/` on commit. The lint hook runs in parallel:
+- **Python**: `ruff check --fix`, `ruff format`, `ty check`
+- **TypeScript**: `eslint --fix`, `prettier`
+
+#### Manual linting and formatting
+
+```bash
+# Run all lints (same as pre-commit)
+./scripts/hooks/lint.sh
+
+# Or run individually for Python:
+cd hindsight-api
+uv run ruff check --fix .   # Lint and auto-fix
+uv run ruff format .        # Format code
+uv run ty check hindsight_api  # Type check
+```
+
+#### Style guidelines
 
 - Use Python type hints
 - Follow existing code patterns

README.md

@@ -5,7 +5,7 @@
 [Documentation](https://hindsight.vectorize.io) • [Paper](https://arxiv.org/abs/2512.12818) • [Cookbook](https://hindsight.vectorize.io/cookbook) • [Hindsight Cloud](https://vectorize.io/hindsight/cloud)
 
 [![CI](https://github.com/vectorize-io/hindsight/actions/workflows/release.yml/badge.svg)](https://github.com/vectorize-io/hindsight/actions/workflows/release.yml)
-[![Slack Community](https://img.shields.io/badge/Slack-Join%20Community-4A154B?logo=slack)](https://join.slack.com/t/hindsight-space/shared_invite/zt-3klo21kua-VUCC_zHP5rIcXFB1_5yw6A)
+[![Slack Community](https://img.shields.io/badge/Slack-Join%20Community-4A154B?logo=slack)](https://join.slack.com/t/hindsight-space/shared_invite/zt-3nhbm4w29-LeSJ5Ixi6j8PdiYOCPlOgg)
 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
 ![PyPI - Downloads](https://img.shields.io/pypi/dm/hindsight-api?label=PyPI)
 ![NPM Downloads](https://img.shields.io/npm/dm/%40vectorize-io%2Fhindsight-client?logoColor=orange&label=NPM&color=blue&link=https%3A%2F%2Fwww.npmjs.com%2Fpackage%2F%40vectorize-io%2Fhindsight-client)
@@ -81,6 +81,8 @@ docker run --rm -it --pull always -p 8888:8888 -p 9999:9999 \
   ghcr.io/vectorize-io/hindsight:latest
 ```
 
+You can modify the LLM provider by setting `HINDSIGHT_API_LLM_PROVIDER`. Valid options are `openai`, `anthropic`, `gemini`, `groq`, `ollama`, and `lmstudio`. The documentation provides more details on [supported models](https://hindsight.vectorize.io/developer/models).
+
 API: http://localhost:8888  
 UI: http://localhost:9999
 
@@ -240,7 +242,7 @@ client.reflect(bank_id="my-bank", query="What should I know about Alice?")
 - [CLI](https://hindsight.vectorize.io/sdks/cli)
 
 **Community:**
-- [Slack](https://join.slack.com/t/hindsight-space/shared_invite/zt-3klo21kua-VUCC_zHP5rIcXFB1_5yw6A)
+- [Slack](https://join.slack.com/t/hindsight-space/shared_invite/zt-3nhbm4w29-LeSJ5Ixi6j8PdiYOCPlOgg)
 - [GitHub Issues](https://github.com/vectorize-io/hindsight/issues)
 
 ---

docker/standalone/Dockerfile

@@ -2,16 +2,24 @@
 # Supports building API-only, Control Plane-only, or both
 #
 # Build args:
-#   INCLUDE_API=true/false  - Include API (default: true)
-#   INCLUDE_CP=true/false   - Include Control Plane (default: true)
+#   INCLUDE_API=true/false         - Include API (default: true)
+#   INCLUDE_CP=true/false          - Include Control Plane (default: true)
+#   INCLUDE_LOCAL_MODELS=true/false - Include local ML models for embeddings/reranking (default: true)
+#                                     Set to false when using external providers (TEI, OpenAI, Cohere)
+#   PRELOAD_ML_MODELS=true/false   - Pre-download ML models during build (default: true)
+#                                     Only effective when INCLUDE_LOCAL_MODELS=true
 #
 # Examples:
-#   docker build -t hindsight .                                    # Both (standalone)
-#   docker build -t hindsight-api --build-arg INCLUDE_CP=false .   # API only
-#   docker build -t hindsight-cp --build-arg INCLUDE_API=false .   # Control Plane only
+#   docker build -t hindsight .                                          # Both (standalone)
+#   docker build -t hindsight-api --build-arg INCLUDE_CP=false .         # API only
+#   docker build -t hindsight-cp --build-arg INCLUDE_API=false .         # Control Plane only
+#   docker build -t hindsight --build-arg PRELOAD_ML_MODELS=false .      # Skip ML model preload
+#   docker build -t hindsight --build-arg INCLUDE_LOCAL_MODELS=false .   # Skip local ML deps (for external providers)
 
 ARG INCLUDE_API=true
 ARG INCLUDE_CP=true
+ARG PRELOAD_ML_MODELS=true
+ARG INCLUDE_LOCAL_MODELS=true
 
 # =============================================================================
 # Stage: API Builder
@@ -19,6 +27,7 @@ ARG INCLUDE_CP=true
 FROM python:3.11-slim AS api-builder
 
 ARG INCLUDE_API
+ARG INCLUDE_LOCAL_MODELS
 RUN if [ "$INCLUDE_API" != "true" ]; then echo "Skipping API build" && exit 0; fi
 
 WORKDIR /app
@@ -37,6 +46,15 @@ COPY hindsight-api/README.md ./api/
 
 WORKDIR /app/api
 
+# Remove local ML model dependencies if INCLUDE_LOCAL_MODELS=false
+# This creates a smaller image when using external providers (TEI, OpenAI, Cohere)
+RUN if [ "$INCLUDE_LOCAL_MODELS" != "true" ]; then \
+        echo "Removing local-models dependencies (sentence-transformers, torch, transformers)..." && \
+        sed -i '/"sentence-transformers/d' pyproject.toml && \
+        sed -i '/"transformers/d' pyproject.toml && \
+        sed -i '/"torch/d' pyproject.toml; \
+    fi
+
 # Sync dependencies (will create lock file if needed)
 RUN uv sync
 
@@ -122,7 +140,6 @@ FROM python:3.11-slim AS api-only
 
 WORKDIR /app
 
-# Install pg0 dependencies (procps provides 'kill' command needed by pg0)
 # Note: libicu version varies by Debian version - try common versions in order
 RUN apt-get update && apt-get install -y \
     curl \
@@ -135,7 +152,6 @@ RUN apt-get update && apt-get install -y \
     && rm -rf /var/lib/apt/lists/* \
     && pip install --no-cache-dir uv
 
-# Create non-root user (PostgreSQL cannot run as root)
 RUN useradd -m -s /bin/bash hindsight
 
 # Copy API with virtual environment from builder
@@ -145,28 +161,26 @@ COPY --from=api-builder /app/api /app/api
 COPY docker/standalone/start-all.sh /app/start-all.sh
 RUN chmod +x /app/start-all.sh
 
-# Create data directory for pg0 and set ownership
-RUN mkdir -p /app/data && chown -R hindsight:hindsight /app
+RUN chown -R hindsight:hindsight /app
 
-# Switch to non-root user
 USER hindsight
 
-# Set PATH for hindsight user
 ENV PATH="/app/api/.venv/bin:${PATH}"
 
-# Pre-cache PostgreSQL binaries by starting/stopping pg0-embedded
-ENV PG0_HOME=/home/hindsight/.pg0-cache
-
-ENV PG0_HOME=/home/hindsight/.pg0
-
-# Pre-download ML models to avoid runtime download
-RUN /app/api/.venv/bin/python -c "\
+# Pre-download ML models to avoid runtime download (conditional)
+# Only runs if both PRELOAD_ML_MODELS=true AND INCLUDE_LOCAL_MODELS=true
+ARG PRELOAD_ML_MODELS
+ARG INCLUDE_LOCAL_MODELS
+RUN if [ "$PRELOAD_ML_MODELS" = "true" ] && [ "$INCLUDE_LOCAL_MODELS" = "true" ]; then \
+    /app/api/.venv/bin/python -c "\
 from sentence_transformers import SentenceTransformer, CrossEncoder; \
 print('Downloading embedding model...'); \
 SentenceTransformer('BAAI/bge-small-en-v1.5'); \
 print('Downloading cross-encoder model...'); \
 CrossEncoder('cross-encoder/ms-marco-MiniLM-L-6-v2'); \
-print('Models cached successfully')"
+print('Models cached successfully')"; \
+    elif [ "$INCLUDE_LOCAL_MODELS" != "true" ]; then echo "Skipping ML model preload (local-models not included)"; \
+    else echo "Skipping ML model preload"; fi
 
 EXPOSE 8888
 
@@ -220,7 +234,7 @@ FROM python:3.11-slim AS standalone
 
 WORKDIR /app
 
-# Install Node.js, curl, uv, and pg0 dependencies (procps provides 'kill' command needed by pg0)
+# Install Node.js, curl, uv, and system dependencies
 # Note: libicu version varies by Debian version - try common versions in order
 RUN apt-get update && apt-get install -y \
     curl \
@@ -235,7 +249,6 @@ RUN apt-get update && apt-get install -y \
     && rm -rf /var/lib/apt/lists/* \
     && pip install --no-cache-dir uv
 
-# Create non-root user (PostgreSQL cannot run as root)
 RUN useradd -m -s /bin/bash hindsight
 
 # Copy API with virtual environment from builder
@@ -256,35 +269,26 @@ WORKDIR /app
 COPY docker/standalone/start-all.sh /app/start-all.sh
 RUN chmod +x /app/start-all.sh
 
-# Create data directory for pg0 and set ownership
-RUN mkdir -p /app/data && chown -R hindsight:hindsight /app
+RUN chown -R hindsight:hindsight /app
 
-# Switch to non-root user
 USER hindsight
 
-# Set PATH for hindsight user
 ENV PATH="/app/api/.venv/bin:${PATH}"
 
-# Pre-cache PostgreSQL binaries by starting/stopping pg0-embedded
-ENV PG0_HOME=/home/hindsight/.pg0-cache
-RUN /app/api/.venv/bin/python -c "\
-from pg0 import Pg0; \
-print('Pre-caching PostgreSQL binaries...'); \
-pg = Pg0(name='hindsight', port=5555, username='hindsight', password='hindsight', database='hindsight'); \
-pg.start(); \
-pg.stop(); \
-print('PostgreSQL pre-cached to PG0_HOME')" || echo "Pre-download skipped"
-
-ENV PG0_HOME=/home/hindsight/.pg0
-
-# Pre-download ML models to avoid runtime download
-RUN /app/api/.venv/bin/python -c "\
+# Pre-download ML models to avoid runtime download (conditional)
+# Only runs if both PRELOAD_ML_MODELS=true AND INCLUDE_LOCAL_MODELS=true
+ARG PRELOAD_ML_MODELS
+ARG INCLUDE_LOCAL_MODELS
+RUN if [ "$PRELOAD_ML_MODELS" = "true" ] && [ "$INCLUDE_LOCAL_MODELS" = "true" ]; then \
+    /app/api/.venv/bin/python -c "\
 from sentence_transformers import SentenceTransformer, CrossEncoder; \
 print('Downloading embedding model...'); \
 SentenceTransformer('BAAI/bge-small-en-v1.5'); \
 print('Downloading cross-encoder model...'); \
 CrossEncoder('cross-encoder/ms-marco-MiniLM-L-6-v2'); \
-print('Models cached successfully')"
+print('Models cached successfully')"; \
+    elif [ "$INCLUDE_LOCAL_MODELS" != "true" ]; then echo "Skipping ML model preload (local-models not included)"; \
+    else echo "Skipping ML model preload"; fi
 
 EXPOSE 8888 9999
 

docker/standalone/start-all.sh

@@ -5,16 +5,70 @@ set -e
 ENABLE_API="${HINDSIGHT_ENABLE_API:-true}"
 ENABLE_CP="${HINDSIGHT_ENABLE_CP:-true}"
 
-# Copy pre-cached PostgreSQL data if runtime directory is empty (first run with volume)
-if [ "$ENABLE_API" = "true" ]; then
-    PG0_CACHE="/home/hindsight/.pg0-cache"
-    PG0_HOME="/home/hindsight/.pg0"
-    if [ -d "$PG0_CACHE" ] && [ "$(ls -A $PG0_CACHE 2>/dev/null)" ]; then
-        if [ ! "$(ls -A $PG0_HOME 2>/dev/null)" ]; then
-            echo "📦 Copying pre-cached PostgreSQL data..."
-            cp -r "$PG0_CACHE"/* "$PG0_HOME"/ 2>/dev/null || true
-        fi
+# =============================================================================
+# Dependency waiting (opt-in via HINDSIGHT_WAIT_FOR_DEPS=true)
+#
+# Problem: When running with LM Studio, the LLM may take time to load models.
+# If Hindsight starts before LM Studio is ready, it fails on LLM verification.
+# This wait loop ensures dependencies are ready before starting.
+# =============================================================================
+if [ "${HINDSIGHT_WAIT_FOR_DEPS:-false}" = "true" ]; then
+    LLM_BASE_URL="${HINDSIGHT_API_LLM_BASE_URL:-http://host.docker.internal:1234/v1}"
+    MAX_RETRIES="${HINDSIGHT_RETRY_MAX:-0}"  # 0 = infinite
+    RETRY_INTERVAL="${HINDSIGHT_RETRY_INTERVAL:-10}"
+
+    # Check if external database is configured (skip check for embedded pg0)
+    SKIP_DB_CHECK=false
+    if [ -z "${HINDSIGHT_API_DATABASE_URL}" ]; then
+        SKIP_DB_CHECK=true
+    else
+        DB_CHECK_HOST=$(echo "$HINDSIGHT_API_DATABASE_URL" | sed -E 's|.*@([^:/]+):([0-9]+)/.*|\1 \2|')
     fi
+
+    check_db() {
+        if $SKIP_DB_CHECK; then
+            return 0
+        fi
+        if command -v pg_isready &> /dev/null; then
+            pg_isready -h $(echo $DB_CHECK_HOST | cut -d' ' -f1) -p $(echo $DB_CHECK_HOST | cut -d' ' -f2) &>/dev/null
+        else
+            python3 -c "import socket; s=socket.socket(); s.settimeout(5); exit(0 if s.connect_ex(('$(echo $DB_CHECK_HOST | cut -d' ' -f1)', $(echo $DB_CHECK_HOST | cut -d' ' -f2))) == 0 else 1)" 2>/dev/null
+        fi
+    }
+
+    check_llm() {
+        curl -sf "${LLM_BASE_URL}/models" --connect-timeout 5 &>/dev/null
+    }
+
+    echo "⏳ Waiting for dependencies to be ready..."
+    attempt=1
+
+    while true; do
+        db_ok=false
+        llm_ok=false
+
+        if check_db; then
+            db_ok=true
+        fi
+
+        if check_llm; then
+            llm_ok=true
+        fi
+
+        if $db_ok && $llm_ok; then
+            echo "✅ Dependencies ready!"
+            break
+        fi
+
+        if [ "$MAX_RETRIES" -ne 0 ] && [ "$attempt" -ge "$MAX_RETRIES" ]; then
+            echo "❌ Max retries ($MAX_RETRIES) reached. Dependencies not available."
+            exit 1
+        fi
+
+        echo "   Attempt $attempt: DB=$( $db_ok && echo 'ok' || echo 'waiting' ), LLM=$( $llm_ok && echo 'ok' || echo 'waiting' )"
+        sleep "$RETRY_INTERVAL"
+        ((attempt++))
+    done
 fi
 
 # Track PIDs for wait

helm/hindsight/Chart.yaml

@@ -2,8 +2,8 @@ apiVersion: v2
 name: hindsight
 description: Hindsight helm chart
 type: application
-version: 0.1.11
-appVersion: "0.1.11"
+version: 0.3.0
+appVersion: "0.3.0"
 keywords:
   - ai
   - memory

helm/hindsight/templates/_helpers.tpl

@@ -110,3 +110,14 @@ API URL for control plane
 {{- define "hindsight.apiUrl" -}}
 {{- printf "http://%s-api:%d" (include "hindsight.fullname" .) (.Values.api.service.port | int) }}
 {{- end }}
+
+{{/*
+Get the name of the secret to use
+*/}}
+{{- define "hindsight.secretName" -}}
+{{- if .Values.existingSecret }}
+{{- .Values.existingSecret }}
+{{- else }}
+{{- printf "%s-secret" (include "hindsight.fullname" .) }}
+{{- end }}
+{{- end }}

helm/hindsight/templates/api-deployment.yaml

@@ -15,7 +15,9 @@ spec:
   template:
     metadata:
       annotations:
+        {{- if not .Values.existingSecret }}
         checksum/secret: {{ include (print $.Template.BasePath "/secret.yaml") . | sha256sum }}
+        {{- end }}
         {{- with .Values.podAnnotations }}
         {{- toYaml . | nindent 8 }}
         {{- end }}
@@ -37,27 +39,36 @@ spec:
         - name: http
           containerPort: {{ .Values.api.service.targetPort }}
           protocol: TCP
+        {{- if .Values.existingSecret }}
+        envFrom:
+        - secretRef:
+            name: {{ .Values.existingSecret }}
+        {{- end }}
         env:
-        - name: HINDSIGHT_API_DATABASE_URL
-          value: {{ include "hindsight.databaseUrl" . | quote }}
+        {{- /* POSTGRES_PASSWORD must be defined before DATABASE_URL for $(VAR) interpolation */}}
         {{- if not .Values.postgresql.enabled }}
         - name: POSTGRES_PASSWORD
           valueFrom:
             secretKeyRef:
-              name: {{ include "hindsight.fullname" . }}-secret
+              name: {{ include "hindsight.secretName" . }}
               key: postgres-password
         {{- end }}
+        - name: HINDSIGHT_API_DATABASE_URL
+          value: {{ include "hindsight.databaseUrl" . | quote }}
         {{- range $key, $value := .Values.api.env }}
         - name: {{ $key }}
           value: {{ $value | quote }}
         {{- end }}
+        {{- /* Only use api.secrets when not using existingSecret (for chart-managed secrets) */}}
+        {{- if not .Values.existingSecret }}
         {{- range $key, $value := .Values.api.secrets }}
         - name: {{ $key }}
           valueFrom:
             secretKeyRef:
-              name: {{ include "hindsight.fullname" $ }}-secret
+              name: {{ include "hindsight.secretName" $ }}
               key: {{ $key }}
         {{- end }}
+        {{- end }}
         livenessProbe:
           {{- toYaml .Values.api.livenessProbe | nindent 10 }}
         readinessProbe:

helm/hindsight/templates/controlplane-deployment.yaml

@@ -15,7 +15,9 @@ spec:
   template:
     metadata:
       annotations:
+        {{- if not .Values.existingSecret }}
         checksum/secret: {{ include (print $.Template.BasePath "/secret.yaml") . | sha256sum }}
+        {{- end }}
         {{- with .Values.podAnnotations }}
         {{- toYaml . | nindent 8 }}
         {{- end }}
@@ -37,6 +39,11 @@ spec:
         - name: http
           containerPort: {{ .Values.controlPlane.service.targetPort }}
           protocol: TCP
+        {{- if .Values.existingSecret }}
+        envFrom:
+        - secretRef:
+            name: {{ .Values.existingSecret }}
+        {{- end }}
         env:
         - name: HINDSIGHT_CP_DATAPLANE_API_URL
           value: {{ include "hindsight.apiUrl" . | quote }}
@@ -44,13 +51,16 @@ spec:
         - name: {{ $key }}
           value: {{ $value | quote }}
         {{- end }}
+        {{- /* Only use controlPlane.secrets when not using existingSecret (for chart-managed secrets) */}}
+        {{- if not .Values.existingSecret }}
         {{- range $key, $value := .Values.controlPlane.secrets }}
         - name: {{ $key }}
           valueFrom:
             secretKeyRef:
-              name: {{ include "hindsight.fullname" $ }}-secret
+              name: {{ include "hindsight.secretName" $ }}
               key: {{ $key }}
         {{- end }}
+        {{- end }}
         livenessProbe:
           {{- toYaml .Values.controlPlane.livenessProbe | nindent 10 }}
         readinessProbe:

helm/hindsight/templates/secret.yaml

@@ -1,7 +1,8 @@
+{{- if not .Values.existingSecret }}
 apiVersion: v1
 kind: Secret
 metadata:
-  name: {{ include "hindsight.fullname" . }}-secret
+  name: {{ include "hindsight.secretName" . }}
   labels:
     {{- include "hindsight.labels" . | nindent 4 }}
 type: Opaque
@@ -15,3 +16,4 @@ data:
   {{- if and (not .Values.postgresql.enabled) .Values.postgresql.external.password }}
   postgres-password: {{ .Values.postgresql.external.password | b64enc | quote }}
   {{- end }}
+{{- end }}

helm/hindsight/values.yaml

@@ -3,6 +3,15 @@
 # Chart version - use this to set a consistent image tag across all components
 version: "0.1.1"
 
+# Use an existing secret instead of creating one from values
+# When set, all keys from this secret are injected as environment variables via envFrom
+# Required keys:
+#   - postgres-password: PostgreSQL password (when postgresql.enabled=false)
+# Optional keys (any key becomes an env var):
+#   - HINDSIGHT_API_LLM_API_KEY: API key for LLM provider
+#   - Any other env vars you want to inject
+# existingSecret: "my-hindsight-secret"
+
 # Global settings
 replicaCount: 1
 

hindsight-api/README.md

@@ -80,7 +80,7 @@ Configure via environment variables:
 | Variable | Description | Default |
 |----------|-------------|---------|
 | `HINDSIGHT_API_DATABASE_URL` | PostgreSQL connection string | `pg0` (embedded) |
-| `HINDSIGHT_API_LLM_PROVIDER` | `openai`, `groq`, `gemini`, `ollama` | `openai` |
+| `HINDSIGHT_API_LLM_PROVIDER` | `openai`, `anthropic`, `gemini`, `groq`, `ollama`, `lmstudio` | `openai` |
 | `HINDSIGHT_API_LLM_API_KEY` | API key for LLM provider | - |
 | `HINDSIGHT_API_LLM_MODEL` | Model name | `gpt-4o-mini` |
 | `HINDSIGHT_API_HOST` | Server bind address | `0.0.0.0` |

hindsight-api/hindsight_api/__init__.py

@@ -21,9 +21,11 @@ from .engine.search.trace import (
     WeightComponents,
 )
 from .engine.search.tracer import SearchTracer
+from .models import RequestContext
 
 __all__ = [
     "MemoryEngine",
+    "RequestContext",
     "HindsightConfig",
     "get_config",
     "SearchTrace",

hindsight-api/hindsight_api/admin/__init__.py

@@ -0,0 +1 @@
+# Admin CLI for Hindsight

hindsight-api/hindsight_api/admin/cli.py

@@ -0,0 +1,252 @@
+"""
+Hindsight Admin CLI - backup and restore operations.
+"""
+
+import asyncio
+import io
+import json
+import logging
+import zipfile
+from datetime import datetime, timezone
+from pathlib import Path
+from typing import Any
+
+import asyncpg
+import typer
+
+from ..config import HindsightConfig
+from ..pg0 import parse_pg0_url, resolve_database_url
+
+
+def _fq_table(table: str, schema: str) -> str:
+    """Get fully-qualified table name with schema prefix."""
+    return f"{schema}.{table}"
+
+
+# Setup logging
+logging.basicConfig(
+    level=logging.INFO,
+    format="%(message)s",
+)
+logger = logging.getLogger(__name__)
+
+app = typer.Typer(name="hindsight-admin", help="Hindsight administrative commands")
+
+# Tables to backup/restore in dependency order
+# Import must happen in this order due to foreign key constraints
+BACKUP_TABLES = [
+    "banks",
+    "documents",
+    "entities",
+    "chunks",
+    "memory_units",
+    "unit_entities",
+    "entity_cooccurrences",
+    "memory_links",
+]
+
+MANIFEST_VERSION = "1"
+
+
+async def _backup(database_url: str, output_path: Path, schema: str = "public") -> dict[str, Any]:
+    """Backup all tables to a zip file using binary COPY protocol."""
+    conn = await asyncpg.connect(database_url)
+    try:
+        tables: dict[str, Any] = {}
+        manifest: dict[str, Any] = {
+            "version": MANIFEST_VERSION,
+            "created_at": datetime.now(timezone.utc).isoformat(),
+            "schema": schema,
+            "tables": tables,
+        }
+
+        # Use a transaction with REPEATABLE READ isolation to get a consistent
+        # snapshot across all tables. This prevents race conditions where
+        # entity_cooccurrences could reference entities created after the
+        # entities table was backed up.
+        async with conn.transaction(isolation="repeatable_read"):
+            with zipfile.ZipFile(output_path, "w", zipfile.ZIP_DEFLATED) as zf:
+                for i, table in enumerate(BACKUP_TABLES, 1):
+                    typer.echo(f"  [{i}/{len(BACKUP_TABLES)}] Backing up {table}...", nl=False)
+
+                    buffer = io.BytesIO()
+
+                    # Use binary COPY for exact type preservation
+                    # asyncpg requires schema_name as separate parameter
+                    await conn.copy_from_table(table, schema_name=schema, output=buffer, format="binary")
+
+                    data = buffer.getvalue()
+                    zf.writestr(f"{table}.bin", data)
+
+                    # Get row count for manifest
+                    qualified_table = _fq_table(table, schema)
+                    row_count = await conn.fetchval(f"SELECT COUNT(*) FROM {qualified_table}")
+                    tables[table] = {
+                        "rows": row_count,
+                        "size_bytes": len(data),
+                    }
+
+                    typer.echo(f" {row_count} rows")
+
+                zf.writestr("manifest.json", json.dumps(manifest, indent=2))
+
+        return manifest
+    finally:
+        await conn.close()
+
+
+async def _restore(database_url: str, input_path: Path, schema: str = "public") -> dict[str, Any]:
+    """Restore all tables from a zip file using binary COPY protocol."""
+    conn = await asyncpg.connect(database_url)
+    try:
+        with zipfile.ZipFile(input_path, "r") as zf:
+            # Read and validate manifest
+            manifest: dict[str, Any] = json.loads(zf.read("manifest.json"))
+            if manifest.get("version") != MANIFEST_VERSION:
+                raise ValueError(f"Unsupported backup version: {manifest.get('version')}")
+
+            # Use a transaction for atomic restore - either all tables are
+            # restored or none are, preventing partial/inconsistent state.
+            async with conn.transaction():
+                typer.echo("  Clearing existing data...")
+                # Truncate tables in reverse order (respects FK constraints)
+                for table in reversed(BACKUP_TABLES):
+                    qualified_table = _fq_table(table, schema)
+                    await conn.execute(f"TRUNCATE TABLE {qualified_table} CASCADE")
+
+                # Restore tables in forward order
+                for i, table in enumerate(BACKUP_TABLES, 1):
+                    filename = f"{table}.bin"
+                    if filename not in zf.namelist():
+                        typer.echo(f"  [{i}/{len(BACKUP_TABLES)}] {table}: skipped (not in backup)")
+                        continue
+
+                    expected_rows = manifest["tables"].get(table, {}).get("rows", "?")
+                    typer.echo(f"  [{i}/{len(BACKUP_TABLES)}] Restoring {table}... {expected_rows} rows")
+
+                    data = zf.read(filename)
+                    buffer = io.BytesIO(data)
+                    # asyncpg requires schema_name as separate parameter
+                    await conn.copy_to_table(table, schema_name=schema, source=buffer, format="binary")
+
+                # Refresh materialized view
+                typer.echo("  Refreshing materialized views...")
+                await conn.execute(f"REFRESH MATERIALIZED VIEW {_fq_table('memory_units_bm25', schema)}")
+
+        return manifest
+    finally:
+        await conn.close()
+
+
+async def _run_backup(db_url: str, output: Path, schema: str = "public") -> dict[str, Any]:
+    """Resolve database URL and run backup."""
+    is_pg0, instance_name, _ = parse_pg0_url(db_url)
+    if is_pg0:
+        typer.echo(f"Starting embedded PostgreSQL (instance: {instance_name})...")
+    resolved_url = await resolve_database_url(db_url)
+    return await _backup(resolved_url, output, schema)
+
+
+async def _run_restore(db_url: str, input_file: Path, schema: str = "public") -> dict[str, Any]:
+    """Resolve database URL and run restore."""
+    is_pg0, instance_name, _ = parse_pg0_url(db_url)
+    if is_pg0:
+        typer.echo(f"Starting embedded PostgreSQL (instance: {instance_name})...")
+    resolved_url = await resolve_database_url(db_url)
+    return await _restore(resolved_url, input_file, schema)
+
+
+@app.command()
+def backup(
+    output: Path = typer.Argument(..., help="Output file path (.zip)"),
+    schema: str = typer.Option("public", "--schema", "-s", help="Database schema to backup"),
+):
+    """Backup the Hindsight database to a zip file."""
+    config = HindsightConfig.from_env()
+
+    if not config.database_url:
+        typer.echo("Error: Database URL not configured.", err=True)
+        typer.echo("Set HINDSIGHT_API_DATABASE_URL environment variable.", err=True)
+        raise typer.Exit(1)
+
+    if output.suffix != ".zip":
+        output = output.with_suffix(".zip")
+
+    typer.echo(f"Backing up database (schema: {schema}) to {output}...")
+
+    manifest = asyncio.run(_run_backup(config.database_url, output, schema))
+
+    total_rows = sum(t["rows"] for t in manifest["tables"].values())
+    typer.echo(f"Backed up {total_rows} rows across {len(BACKUP_TABLES)} tables")
+    typer.echo(f"Backup saved to {output}")
+
+
+@app.command()
+def restore(
+    input_file: Path = typer.Argument(..., help="Input backup file (.zip)"),
+    schema: str = typer.Option("public", "--schema", "-s", help="Database schema to restore to"),
+    yes: bool = typer.Option(False, "--yes", "-y", help="Skip confirmation prompt"),
+):
+    """Restore the database from a backup file. WARNING: This deletes all existing data."""
+    config = HindsightConfig.from_env()
+
+    if not config.database_url:
+        typer.echo("Error: Database URL not configured.", err=True)
+        typer.echo("Set HINDSIGHT_API_DATABASE_URL environment variable.", err=True)
+        raise typer.Exit(1)
+
+    if not input_file.exists():
+        typer.echo(f"Error: File not found: {input_file}", err=True)
+        raise typer.Exit(1)
+
+    if not yes:
+        typer.confirm(
+            "This will DELETE all existing data and replace it with the backup. Continue?",
+            abort=True,
+        )
+
+    typer.echo(f"Restoring database (schema: {schema}) from {input_file}...")
+
+    manifest = asyncio.run(_run_restore(config.database_url, input_file, schema))
+
+    total_rows = sum(t["rows"] for t in manifest["tables"].values())
+    typer.echo(f"Restored {total_rows} rows across {len(BACKUP_TABLES)} tables")
+    typer.echo("Restore complete")
+
+
+async def _run_migration(db_url: str, schema: str = "public") -> None:
+    """Resolve database URL and run migrations."""
+    from ..migrations import run_migrations
+
+    is_pg0, instance_name, _ = parse_pg0_url(db_url)
+    if is_pg0:
+        typer.echo(f"Starting embedded PostgreSQL (instance: {instance_name})...")
+    resolved_url = await resolve_database_url(db_url)
+    run_migrations(resolved_url, schema=schema)
+
+
+@app.command(name="run-db-migration")
+def run_db_migration(
+    schema: str = typer.Option("public", "--schema", "-s", help="Database schema to run migrations on"),
+):
+    """Run database migrations to the latest version."""
+    config = HindsightConfig.from_env()
+
+    if not config.database_url:
+        typer.echo("Error: Database URL not configured.", err=True)
+        typer.echo("Set HINDSIGHT_API_DATABASE_URL environment variable.", err=True)
+        raise typer.Exit(1)
+
+    typer.echo(f"Running database migrations (schema: {schema})...")
+
+    asyncio.run(_run_migration(config.database_url, schema))
+
+    typer.echo("Database migrations completed successfully")
+
+
+def main():
+    app()
+
+
+if __name__ == "__main__":
+    main()

hindsight-api/hindsight_api/alembic/env.py

@@ -109,6 +109,9 @@ def run_migrations_online() -> None:
 
     get_database_url()  # Process and set the database URL in config
 
+    # Check if we're targeting a specific schema (for multi-tenant isolation)
+    target_schema = config.get_main_option("target_schema")
+
     connectable = engine_from_config(
         config.get_section(config.config_ini_section, {}),
         prefix="sqlalchemy.",
@@ -121,14 +124,34 @@ def run_migrations_online() -> None:
     def set_read_write_mode(dbapi_connection, connection_record):
         cursor = dbapi_connection.cursor()
         cursor.execute("SET SESSION CHARACTERISTICS AS TRANSACTION READ WRITE")
+        # If targeting a specific schema, set search_path
+        # Include public in search_path for access to shared extensions (pgvector)
+        if target_schema:
+            cursor.execute(f'CREATE SCHEMA IF NOT EXISTS "{target_schema}"')
+            cursor.execute(f'SET search_path TO "{target_schema}", public')
         cursor.close()
 
     with connectable.connect() as connection:
         # Also explicitly set read-write mode on this connection
         connection.execute(text("SET SESSION CHARACTERISTICS AS TRANSACTION READ WRITE"))
+
+        # If targeting a specific schema, set search_path
+        # Include public in search_path for access to shared extensions (pgvector)
+        if target_schema:
+            connection.execute(text(f'CREATE SCHEMA IF NOT EXISTS "{target_schema}"'))
+            connection.execute(text(f'SET search_path TO "{target_schema}", public'))
+
         connection.commit()  # Commit the SET command
 
-        context.configure(connection=connection, target_metadata=target_metadata)
+        # Configure context with version_table_schema if using a specific schema
+        context_opts = {
+            "connection": connection,
+            "target_metadata": target_metadata,
+        }
+        if target_schema:
+            context_opts["version_table_schema"] = target_schema
+
+        context.configure(**context_opts)
 
         with context.begin_transaction():
             context.run_migrations()

hindsight-api/hindsight_api/alembic/versions/d9f6a3b4c5e2_rename_bank_to_interactions.py

@@ -6,7 +6,7 @@ Create Date: 2024-12-04 15:00:00.000000
 
 """
 
-from alembic import op
+from alembic import context, op
 
 # revision identifiers, used by Alembic.
 revision = "d9f6a3b4c5e2"
@@ -15,14 +15,22 @@ branch_labels = None
 depends_on = None
 
 
+def _get_schema_prefix() -> str:
+    """Get schema prefix for table names (e.g., 'tenant_x.' or '' for public)."""
+    schema = context.config.get_main_option("target_schema")
+    return f'"{schema}".' if schema else ""
+
+
 def upgrade():
+    schema = _get_schema_prefix()
+
     # Drop old check constraint FIRST (before updating data)
     op.drop_constraint("memory_units_fact_type_check", "memory_units", type_="check")
 
     # Update existing 'bank' values to 'experience'
-    op.execute("UPDATE memory_units SET fact_type = 'experience' WHERE fact_type = 'bank'")
+    op.execute(f"UPDATE {schema}memory_units SET fact_type = 'experience' WHERE fact_type = 'bank'")
     # Also update any 'interactions' values (in case of partial migration)
-    op.execute("UPDATE memory_units SET fact_type = 'experience' WHERE fact_type = 'interactions'")
+    op.execute(f"UPDATE {schema}memory_units SET fact_type = 'experience' WHERE fact_type = 'interactions'")
 
     # Create new check constraint with 'experience' instead of 'bank'
     op.create_check_constraint(
@@ -31,11 +39,13 @@ def upgrade():
 
 
 def downgrade():
+    schema = _get_schema_prefix()
+
     # Drop new check constraint FIRST
     op.drop_constraint("memory_units_fact_type_check", "memory_units", type_="check")
 
     # Update 'experience' back to 'bank'
-    op.execute("UPDATE memory_units SET fact_type = 'bank' WHERE fact_type = 'experience'")
+    op.execute(f"UPDATE {schema}memory_units SET fact_type = 'bank' WHERE fact_type = 'experience'")
 
     # Recreate old check constraint
     op.create_check_constraint(

hindsight-api/hindsight_api/alembic/versions/e0a1b2c3d4e5_disposition_to_3_traits.py

@@ -12,7 +12,7 @@ system (skepticism, literalism, empathy with 1-5 integer values).
 from collections.abc import Sequence
 
 import sqlalchemy as sa
-from alembic import op
+from alembic import context, op
 
 # revision identifiers, used by Alembic.
 revision: str = "e0a1b2c3d4e5"
@@ -21,9 +21,36 @@ branch_labels: str | Sequence[str] | None = None
 depends_on: str | Sequence[str] | None = None
 
 
+def _get_schema_prefix() -> str:
+    """Get schema prefix for table names (e.g., 'tenant_x.' or '' for public)."""
+    schema = context.config.get_main_option("target_schema")
+    return f'"{schema}".' if schema else ""
+
+
+def _get_target_schema() -> str:
+    """Get the target schema name (tenant schema or 'public')."""
+    schema = context.config.get_main_option("target_schema")
+    return schema if schema else "public"
+
+
 def upgrade() -> None:
     """Convert Big Five disposition to 3-trait disposition."""
     conn = op.get_bind()
+    schema = _get_schema_prefix()
+    target_schema = _get_target_schema()
+
+    # Check if disposition column exists (should have been created by previous migration)
+    result = conn.execute(
+        sa.text("""
+        SELECT column_name
+        FROM information_schema.columns
+        WHERE table_schema = :schema AND table_name = 'banks' AND column_name = 'disposition'
+    """),
+        {"schema": target_schema},
+    )
+    if not result.fetchone():
+        # Column doesn't exist yet (shouldn't happen but be safe)
+        return
 
     # Update all existing banks to use the new disposition format
     # Convert from old format to new format with reasonable mappings:
@@ -32,18 +59,18 @@ def upgrade() -> None:
     # - empathy: derived from agreeableness + inverse of neuroticism
     # Default all to 3 (neutral) for simplicity
     conn.execute(
-        sa.text("""
-        UPDATE banks
-        SET disposition = '{"skepticism": 3, "literalism": 3, "empathy": 3}'::jsonb
+        sa.text(f"""
+        UPDATE {schema}banks
+        SET disposition = '{{"skepticism": 3, "literalism": 3, "empathy": 3}}'::jsonb
         WHERE disposition IS NOT NULL
     """)
     )
 
     # Update the default for new banks
     conn.execute(
-        sa.text("""
-        ALTER TABLE banks
-        ALTER COLUMN disposition SET DEFAULT '{"skepticism": 3, "literalism": 3, "empathy": 3}'::jsonb
+        sa.text(f"""
+        ALTER TABLE {schema}banks
+        ALTER COLUMN disposition SET DEFAULT '{{"skepticism": 3, "literalism": 3, "empathy": 3}}'::jsonb
     """)
     )
 
@@ -51,20 +78,34 @@ def upgrade() -> None:
 def downgrade() -> None:
     """Convert back to Big Five disposition."""
     conn = op.get_bind()
+    schema = _get_schema_prefix()
+    target_schema = _get_target_schema()
+
+    # Check if disposition column exists
+    result = conn.execute(
+        sa.text("""
+        SELECT column_name
+        FROM information_schema.columns
+        WHERE table_schema = :schema AND table_name = 'banks' AND column_name = 'disposition'
+    """),
+        {"schema": target_schema},
+    )
+    if not result.fetchone():
+        return
 
     # Revert to Big Five format with default values
     conn.execute(
-        sa.text("""
-        UPDATE banks
-        SET disposition = '{"openness": 0.5, "conscientiousness": 0.5, "extraversion": 0.5, "agreeableness": 0.5, "neuroticism": 0.5, "bias_strength": 0.5}'::jsonb
+        sa.text(f"""
+        UPDATE {schema}banks
+        SET disposition = '{{"openness": 0.5, "conscientiousness": 0.5, "extraversion": 0.5, "agreeableness": 0.5, "neuroticism": 0.5, "bias_strength": 0.5}}'::jsonb
         WHERE disposition IS NOT NULL
     """)
     )
 
     # Update the default for new banks
     conn.execute(
-        sa.text("""
-        ALTER TABLE banks
-        ALTER COLUMN disposition SET DEFAULT '{"openness": 0.5, "conscientiousness": 0.5, "extraversion": 0.5, "agreeableness": 0.5, "neuroticism": 0.5, "bias_strength": 0.5}'::jsonb
+        sa.text(f"""
+        ALTER TABLE {schema}banks
+        ALTER COLUMN disposition SET DEFAULT '{{"openness": 0.5, "conscientiousness": 0.5, "extraversion": 0.5, "agreeableness": 0.5, "neuroticism": 0.5, "bias_strength": 0.5}}'::jsonb
     """)
     )

hindsight-api/hindsight_api/alembic/versions/f1a2b3c4d5e6_add_memory_links_composite_index.py

@@ -0,0 +1,44 @@
+"""add_memory_links_from_type_weight_index
+
+Revision ID: f1a2b3c4d5e6
+Revises: e0a1b2c3d4e5
+Create Date: 2025-01-12
+
+Add composite index on memory_links (from_unit_id, link_type, weight DESC)
+to optimize MPFP graph traversal queries that need top-k edges per type.
+"""
+
+from collections.abc import Sequence
+
+from alembic import context, op
+
+# revision identifiers, used by Alembic.
+revision: str = "f1a2b3c4d5e6"
+down_revision: str | Sequence[str] | None = "e0a1b2c3d4e5"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def _get_schema_prefix() -> str:
+    """Get schema prefix for table names (e.g., 'tenant_x.' or '' for public)."""
+    schema = context.config.get_main_option("target_schema")
+    return f'"{schema}".' if schema else ""
+
+
+def upgrade() -> None:
+    """Add composite index for efficient MPFP edge loading."""
+    schema = _get_schema_prefix()
+    # Create composite index for efficient top-k per (from_node, link_type) queries
+    # This enables LATERAL joins to use index-only scans with early termination
+    # Note: Not using CONCURRENTLY here as it requires running outside a transaction
+    # For production with large tables, consider running this manually with CONCURRENTLY
+    op.execute(
+        f"CREATE INDEX IF NOT EXISTS idx_memory_links_from_type_weight "
+        f"ON {schema}memory_links(from_unit_id, link_type, weight DESC)"
+    )
+
+
+def downgrade() -> None:
+    """Remove the composite index."""
+    schema = _get_schema_prefix()
+    op.execute(f"DROP INDEX IF EXISTS {schema}idx_memory_links_from_type_weight")

hindsight-api/hindsight_api/alembic/versions/g2a3b4c5d6e7_add_tags_column.py

@@ -0,0 +1,48 @@
+"""add_tags_column
+
+Revision ID: g2a3b4c5d6e7
+Revises: f1a2b3c4d5e6
+Create Date: 2025-01-13
+
+Add tags column to memory_units and documents tables for visibility scoping.
+Tags enable filtering memories by scope (e.g., user IDs, session IDs) during recall/reflect.
+"""
+
+from collections.abc import Sequence
+
+from alembic import context, op
+
+# revision identifiers, used by Alembic.
+revision: str = "g2a3b4c5d6e7"
+down_revision: str | Sequence[str] | None = "f1a2b3c4d5e6"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def _get_schema_prefix() -> str:
+    """Get schema prefix for table names (e.g., 'tenant_x.' or '' for public)."""
+    schema = context.config.get_main_option("target_schema")
+    return f'"{schema}".' if schema else ""
+
+
+def upgrade() -> None:
+    """Add tags column to memory_units and documents tables."""
+    schema = _get_schema_prefix()
+
+    # Add tags column to memory_units table
+    op.execute(f"ALTER TABLE {schema}memory_units ADD COLUMN IF NOT EXISTS tags VARCHAR[] NOT NULL DEFAULT '{{}}'")
+
+    # Create GIN index for efficient array containment queries (tags && ARRAY['x'])
+    op.execute(f"CREATE INDEX IF NOT EXISTS idx_memory_units_tags ON {schema}memory_units USING GIN (tags)")
+
+    # Add tags column to documents table for document-level tags
+    op.execute(f"ALTER TABLE {schema}documents ADD COLUMN IF NOT EXISTS tags VARCHAR[] NOT NULL DEFAULT '{{}}'")
+
+
+def downgrade() -> None:
+    """Remove tags columns and index."""
+    schema = _get_schema_prefix()
+
+    op.execute(f"DROP INDEX IF EXISTS {schema}idx_memory_units_tags")
+    op.execute(f"ALTER TABLE {schema}memory_units DROP COLUMN IF EXISTS tags")
+    op.execute(f"ALTER TABLE {schema}documents DROP COLUMN IF EXISTS tags")

hindsight-api/hindsight_api/alembic/versions/h3c4d5e6f7g8_mental_models_v4.py

@@ -0,0 +1,112 @@
+"""mental_models_v4
+
+Revision ID: h3c4d5e6f7g8
+Revises: g2a3b4c5d6e7
+Create Date: 2026-01-08 00:00:00.000000
+
+This migration implements the v4 mental models system:
+1. Deletes existing observation memory_units (observations now in mental models)
+2. Adds mission column to banks (replacing background)
+3. Creates mental_models table with final schema
+
+Mental models can reference entities when an entity is "promoted" to a mental model.
+Summary content is stored as JSONB observations with per-observation fact attribution.
+"""
+
+from collections.abc import Sequence
+
+from alembic import context, op
+
+# revision identifiers, used by Alembic.
+revision: str = "h3c4d5e6f7g8"
+down_revision: str | Sequence[str] | None = "g2a3b4c5d6e7"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def _get_schema_prefix() -> str:
+    """Get schema prefix for table names (required for multi-tenant support)."""
+    schema = context.config.get_main_option("target_schema")
+    return f'"{schema}".' if schema else ""
+
+
+def upgrade() -> None:
+    """Apply mental models v4 changes."""
+    schema = _get_schema_prefix()
+
+    # Step 1: Delete observation memory_units (cascades to unit_entities links)
+    # Observations are now handled through mental models, not memory_units
+    op.execute(f"DELETE FROM {schema}memory_units WHERE fact_type = 'observation'")
+
+    # Step 2: Drop observation-specific index (if it exists)
+    op.execute(f"DROP INDEX IF EXISTS {schema}idx_memory_units_observation_date")
+
+    # Step 3: Add mission column to banks (replacing background)
+    op.execute(f"ALTER TABLE {schema}banks ADD COLUMN IF NOT EXISTS mission TEXT")
+
+    # Migrate: copy background to mission if background column exists
+    # Use DO block to check column existence first (idempotent for re-runs)
+    schema_name = context.config.get_main_option("target_schema") or "public"
+    op.execute(f"""
+        DO $$
+        BEGIN
+            IF EXISTS (
+                SELECT 1 FROM information_schema.columns
+                WHERE table_schema = '{schema_name}' AND table_name = 'banks' AND column_name = 'background'
+            ) THEN
+                UPDATE {schema}banks
+                SET mission = background
+                WHERE mission IS NULL;
+            END IF;
+        END $$;
+    """)
+
+    # Remove background column (replaced by mission)
+    op.execute(f"ALTER TABLE {schema}banks DROP COLUMN IF EXISTS background")
+
+    # Step 4: Create mental_models table with final v4 schema (if not exists)
+    op.execute(f"""
+        CREATE TABLE IF NOT EXISTS {schema}mental_models (
+            id VARCHAR(64) NOT NULL,
+            bank_id VARCHAR(64) NOT NULL,
+            subtype VARCHAR(32) NOT NULL,
+            name VARCHAR(256) NOT NULL,
+            description TEXT NOT NULL,
+            entity_id UUID,
+            observations JSONB DEFAULT '{{"observations": []}}'::jsonb,
+            links VARCHAR[],
+            tags VARCHAR[] DEFAULT '{{}}',
+            last_updated TIMESTAMP WITH TIME ZONE,
+            created_at TIMESTAMP WITH TIME ZONE NOT NULL DEFAULT now(),
+            PRIMARY KEY (id, bank_id),
+            FOREIGN KEY (bank_id) REFERENCES {schema}banks(bank_id) ON DELETE CASCADE,
+            FOREIGN KEY (entity_id) REFERENCES {schema}entities(id) ON DELETE SET NULL,
+            CONSTRAINT ck_mental_models_subtype CHECK (subtype IN ('structural', 'emergent', 'pinned', 'learned'))
+        )
+    """)
+
+    # Step 5: Create indexes for efficient queries (if not exist)
+    op.execute(f"CREATE INDEX IF NOT EXISTS idx_mental_models_bank_id ON {schema}mental_models(bank_id)")
+    op.execute(f"CREATE INDEX IF NOT EXISTS idx_mental_models_subtype ON {schema}mental_models(bank_id, subtype)")
+    op.execute(f"CREATE INDEX IF NOT EXISTS idx_mental_models_entity_id ON {schema}mental_models(entity_id)")
+    # GIN index for efficient tags array filtering
+    op.execute(f"CREATE INDEX IF NOT EXISTS idx_mental_models_tags ON {schema}mental_models USING GIN(tags)")
+
+
+def downgrade() -> None:
+    """Revert mental models v4 changes."""
+    schema = _get_schema_prefix()
+
+    # Drop mental_models table (cascades to indexes)
+    op.execute(f"DROP TABLE IF EXISTS {schema}mental_models CASCADE")
+
+    # Add back background column to banks
+    op.execute(f"ALTER TABLE {schema}banks ADD COLUMN IF NOT EXISTS background TEXT")
+
+    # Migrate mission back to background
+    op.execute(f"UPDATE {schema}banks SET background = mission WHERE background IS NULL")
+
+    # Remove mission column
+    op.execute(f"ALTER TABLE {schema}banks DROP COLUMN IF EXISTS mission")
+
+    # Note: Cannot restore deleted observations - they are lost on downgrade

hindsight-api/hindsight_api/alembic/versions/i4d5e6f7g8h9_delete_opinions.py

@@ -0,0 +1,41 @@
+"""delete_opinions
+
+Revision ID: i4d5e6f7g8h9
+Revises: h3c4d5e6f7g8
+Create Date: 2026-01-15 00:00:00.000000
+
+This migration removes opinion facts from memory_units.
+Opinions are no longer a separate fact type - they are now represented
+through mental model observations with confidence scores.
+"""
+
+from collections.abc import Sequence
+
+from alembic import context, op
+
+# revision identifiers, used by Alembic.
+revision: str = "i4d5e6f7g8h9"
+down_revision: str | Sequence[str] | None = "h3c4d5e6f7g8"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def _get_schema_prefix() -> str:
+    """Get schema prefix for table names (required for multi-tenant support)."""
+    schema = context.config.get_main_option("target_schema")
+    return f'"{schema}".' if schema else ""
+
+
+def upgrade() -> None:
+    """Delete opinion memory_units."""
+    schema = _get_schema_prefix()
+
+    # Delete opinion memory_units (cascades to unit_entities links)
+    # Opinions are now handled through mental model observations
+    op.execute(f"DELETE FROM {schema}memory_units WHERE fact_type = 'opinion'")
+
+
+def downgrade() -> None:
+    """Cannot restore deleted opinions."""
+    # Note: Cannot restore deleted opinions - they are lost on downgrade
+    pass

hindsight-api/hindsight_api/alembic/versions/rename_personality_to_disposition.py

@@ -9,7 +9,7 @@ Create Date: 2024-12-04
 from collections.abc import Sequence
 
 import sqlalchemy as sa
-from alembic import op
+from alembic import context, op
 from sqlalchemy.dialects import postgresql
 
 # revision identifiers, used by Alembic.
@@ -19,17 +19,25 @@ branch_labels: str | Sequence[str] | None = None
 depends_on: str | Sequence[str] | None = None
 
 
+def _get_target_schema() -> str:
+    """Get the target schema name (tenant schema or 'public')."""
+    schema = context.config.get_main_option("target_schema")
+    return schema if schema else "public"
+
+
 def upgrade() -> None:
     """Rename personality column to disposition in banks table (if it exists)."""
     conn = op.get_bind()
+    target_schema = _get_target_schema()
 
     # Check if 'personality' column exists (old database)
     result = conn.execute(
         sa.text("""
         SELECT column_name
         FROM information_schema.columns
-        WHERE table_name = 'banks' AND column_name = 'personality'
-    """)
+        WHERE table_schema = :schema AND table_name = 'banks' AND column_name = 'personality'
+    """),
+        {"schema": target_schema},
     )
     has_personality = result.fetchone() is not None
 
@@ -38,8 +46,9 @@ def upgrade() -> None:
         sa.text("""
         SELECT column_name
         FROM information_schema.columns
-        WHERE table_name = 'banks' AND column_name = 'disposition'
-    """)
+        WHERE table_schema = :schema AND table_name = 'banks' AND column_name = 'disposition'
+    """),
+        {"schema": target_schema},
     )
     has_disposition = result.fetchone() is not None
 
@@ -63,12 +72,14 @@ def upgrade() -> None:
 def downgrade() -> None:
     """Revert disposition column back to personality."""
     conn = op.get_bind()
+    target_schema = _get_target_schema()
     result = conn.execute(
         sa.text("""
         SELECT column_name
         FROM information_schema.columns
-        WHERE table_name = 'banks' AND column_name = 'disposition'
-    """)
+        WHERE table_schema = :schema AND table_name = 'banks' AND column_name = 'disposition'
+    """),
+        {"schema": target_schema},
     )
     if result.fetchone():
         op.alter_column("banks", "disposition", new_column_name="personality")

hindsight-api/hindsight_api/api/__init__.py

@@ -5,6 +5,7 @@ Provides both HTTP REST API and MCP (Model Context Protocol) server.
 """
 
 import logging
+from contextlib import asynccontextmanager
 from typing import Optional
 
 from fastapi import FastAPI
@@ -45,6 +46,18 @@ def create_app(
         # Both HTTP and MCP
         app = create_app(memory, mcp_api_enabled=True)
     """
+    mcp_app = None
+
+    # Create MCP app first if enabled (we need its lifespan for chaining)
+    if mcp_api_enabled:
+        try:
+            from .mcp import create_mcp_app
+
+            mcp_app = create_mcp_app(memory=memory)
+        except ImportError as e:
+            logger.error(f"MCP server requested but dependencies not available: {e}")
+            logger.error("Install with: pip install hindsight-api[mcp]")
+            raise
 
     # Import and create HTTP API if enabled
     if http_api_enabled:
@@ -57,20 +70,31 @@ def create_app(
         app = FastAPI(title="Hindsight API", version="0.0.7")
         logger.info("HTTP REST API disabled")
 
-    # Mount MCP server if enabled
-    if mcp_api_enabled:
-        try:
-            from .mcp import create_mcp_app
+    # Mount MCP server and chain its lifespan if enabled
+    if mcp_app is not None:
+        # Get the MCP app's underlying Starlette app for lifespan access
+        mcp_starlette_app = mcp_app.mcp_app
 
-            # Create MCP app with dynamic bank_id support
-            # Supports: /mcp/{bank_id}/sse (bank-specific SSE endpoint)
-            mcp_app = create_mcp_app(memory=memory)
-            app.mount(mcp_mount_path, mcp_app)
-            logger.info(f"MCP server enabled at {mcp_mount_path}/{{bank_id}}/sse")
-        except ImportError as e:
-            logger.error(f"MCP server requested but dependencies not available: {e}")
-            logger.error("Install with: pip install hindsight-api[mcp]")
-            raise
+        # Store the original lifespan
+        original_lifespan = app.router.lifespan_context
+
+        @asynccontextmanager
+        async def chained_lifespan(app_instance: FastAPI):
+            """Chain the MCP lifespan with the main app lifespan."""
+            # Start MCP lifespan first
+            async with mcp_starlette_app.router.lifespan_context(mcp_starlette_app):
+                logger.info("MCP lifespan started")
+                # Then start the original app lifespan
+                async with original_lifespan(app_instance):
+                    yield
+            logger.info("MCP lifespan stopped")
+
+        # Replace the app's lifespan with the chained version
+        app.router.lifespan_context = chained_lifespan
+
+        # Mount the MCP middleware
+        app.mount(mcp_mount_path, mcp_app)
+        logger.info(f"MCP server enabled at {mcp_mount_path}/")
 
     return app
 

hindsight-api/hindsight_api/api/mcp.py

@@ -9,6 +9,7 @@ from fastmcp import FastMCP
 
 from hindsight_api import MemoryEngine
 from hindsight_api.engine.response_models import VALID_RECALL_FACT_TYPES
+from hindsight_api.models import RequestContext
 
 # Configure logging from HINDSIGHT_API_LOG_LEVEL environment variable
 _log_level_str = os.environ.get("HINDSIGHT_API_LOG_LEVEL", "info").lower()
@@ -26,12 +27,15 @@ logging.basicConfig(
 )
 logger = logging.getLogger(__name__)
 
-# Context variable to hold the current bank_id from the URL path
+# Default bank_id from environment variable
+DEFAULT_BANK_ID = os.environ.get("HINDSIGHT_MCP_BANK_ID", "default")
+
+# Context variable to hold the current bank_id
 _current_bank_id: ContextVar[str | None] = ContextVar("current_bank_id", default=None)
 
 
 def get_current_bank_id() -> str | None:
-    """Get the current bank_id from context (set from URL path)."""
+    """Get the current bank_id from context."""
     return _current_bank_id.get()
 
 
@@ -43,12 +47,18 @@ def create_mcp_server(memory: MemoryEngine) -> FastMCP:
         memory: MemoryEngine instance (required)
 
     Returns:
-        Configured FastMCP server instance
+        Configured FastMCP server instance with stateless_http enabled
     """
-    mcp = FastMCP("hindsight-mcp-server")
+    # Use stateless_http=True for Claude Code compatibility
+    mcp = FastMCP("hindsight-mcp-server", stateless_http=True)
 
     @mcp.tool()
-    async def retain(content: str, context: str = "general") -> str:
+    async def retain(
+        content: str,
+        context: str = "general",
+        async_processing: bool = True,
+        bank_id: str | None = None,
+    ) -> str:
         """
         Store important information to long-term memory.
 
@@ -64,17 +74,34 @@ def create_mcp_server(memory: MemoryEngine) -> FastMCP:
         Args:
             content: The fact/memory to store (be specific and include relevant details)
             context: Category for the memory (e.g., 'preferences', 'work', 'hobbies', 'family'). Default: 'general'
+            async_processing: If True, queue for background processing and return immediately. If False, wait for completion. Default: True
+            bank_id: Optional bank to store in (defaults to session bank). Use for cross-bank operations.
         """
         try:
-            bank_id = get_current_bank_id()
-            await memory.retain_batch_async(bank_id=bank_id, contents=[{"content": content, "context": context}])
-            return "Memory stored successfully"
+            target_bank = bank_id or get_current_bank_id()
+            if target_bank is None:
+                return "Error: No bank_id configured"
+            contents = [{"content": content, "context": context}]
+            if async_processing:
+                # Queue for background processing and return immediately
+                result = await memory.submit_async_retain(
+                    bank_id=target_bank, contents=contents, request_context=RequestContext()
+                )
+                return f"Memory queued for background processing (operation_id: {result.get('operation_id', 'N/A')})"
+            else:
+                # Wait for completion
+                await memory.retain_batch_async(
+                    bank_id=target_bank,
+                    contents=contents,
+                    request_context=RequestContext(),
+                )
+                return f"Memory stored successfully in bank '{target_bank}'"
         except Exception as e:
             logger.error(f"Error storing memory: {e}", exc_info=True)
             return f"Error: {str(e)}"
 
     @mcp.tool()
-    async def recall(query: str, max_results: int = 10) -> str:
+    async def recall(query: str, max_tokens: int = 4096, bank_id: str | None = None) -> str:
         """
         Search memories to provide personalized, context-aware responses.
 
@@ -86,43 +113,165 @@ def create_mcp_server(memory: MemoryEngine) -> FastMCP:
 
         Args:
             query: Natural language search query (e.g., "user's food preferences", "what projects is user working on")
-            max_results: Maximum number of results to return (default: 10)
+            max_tokens: Maximum tokens in the response (default: 4096)
+            bank_id: Optional bank to search in (defaults to session bank). Use for cross-bank operations.
         """
         try:
-            bank_id = get_current_bank_id()
+            target_bank = bank_id or get_current_bank_id()
+            if target_bank is None:
+                return "Error: No bank_id configured"
             from hindsight_api.engine.memory_engine import Budget
 
-            search_result = await memory.recall_async(
-                bank_id=bank_id, query=query, fact_type=list(VALID_RECALL_FACT_TYPES), budget=Budget.LOW
+            recall_result = await memory.recall_async(
+                bank_id=target_bank,
+                query=query,
+                fact_type=list(VALID_RECALL_FACT_TYPES),
+                budget=Budget.HIGH,
+                max_tokens=max_tokens,
+                request_context=RequestContext(),
             )
 
-            results = [
-                {
-                    "id": fact.id,
-                    "text": fact.text,
-                    "type": fact.fact_type,
-                    "context": fact.context,
-                    "event_date": fact.event_date,
-                }
-                for fact in search_result.results[:max_results]
-            ]
-
-            return json.dumps({"results": results}, indent=2)
+            # Use model's JSON serialization
+            return recall_result.model_dump_json(indent=2)
         except Exception as e:
             logger.error(f"Error searching: {e}", exc_info=True)
-            return json.dumps({"error": str(e), "results": []})
+            return f'{{"error": "{e}", "results": []}}'
+
+    @mcp.tool()
+    async def reflect(query: str, context: str | None = None, budget: str = "low", bank_id: str | None = None) -> str:
+        """
+        Generate thoughtful analysis by synthesizing stored memories with the bank's personality.
+
+        WHEN TO USE THIS TOOL:
+        Use reflect when you need reasoned analysis, not just fact retrieval. This tool
+        thinks through the question using everything the bank knows and its personality traits.
+
+        EXAMPLES OF GOOD QUERIES:
+        - "What patterns have emerged in how I approach debugging?"
+        - "Based on my past decisions, what architectural style do I prefer?"
+        - "What might be the best approach for this problem given what you know about me?"
+        - "How should I prioritize these tasks based on my goals?"
+
+        HOW IT DIFFERS FROM RECALL:
+        - recall: Returns raw facts matching your search (fast lookup)
+        - reflect: Reasons across memories to form a synthesized answer (deeper analysis)
+
+        Use recall for "what did I say about X?" and reflect for "what should I do about X?"
+
+        Args:
+            query: The question or topic to reflect on
+            context: Optional context about why this reflection is needed
+            budget: Search budget - 'low', 'mid', or 'high' (default: 'low')
+            bank_id: Optional bank to reflect in (defaults to session bank). Use for cross-bank operations.
+        """
+        try:
+            target_bank = bank_id or get_current_bank_id()
+            if target_bank is None:
+                return "Error: No bank_id configured"
+            from hindsight_api.engine.memory_engine import Budget
+
+            # Map string budget to enum
+            budget_map = {"low": Budget.LOW, "mid": Budget.MID, "high": Budget.HIGH}
+            budget_enum = budget_map.get(budget.lower(), Budget.LOW)
+
+            reflect_result = await memory.reflect_async(
+                bank_id=target_bank,
+                query=query,
+                budget=budget_enum,
+                context=context,
+                request_context=RequestContext(),
+            )
+
+            return reflect_result.model_dump_json(indent=2)
+        except Exception as e:
+            logger.error(f"Error reflecting: {e}", exc_info=True)
+            return f'{{"error": "{e}", "text": ""}}'
+
+    @mcp.tool()
+    async def list_banks() -> str:
+        """
+        List all available memory banks.
+
+        Use this tool to discover what memory banks exist in the system.
+        Each bank is an isolated memory store (like a separate "brain").
+
+        Returns:
+            JSON list of banks with their IDs, names, dispositions, and missions.
+        """
+        try:
+            banks = await memory.list_banks(request_context=RequestContext())
+            return json.dumps({"banks": banks}, indent=2)
+        except Exception as e:
+            logger.error(f"Error listing banks: {e}", exc_info=True)
+            return f'{{"error": "{e}", "banks": []}}'
+
+    @mcp.tool()
+    async def create_bank(bank_id: str, name: str | None = None, mission: str | None = None) -> str:
+        """
+        Create a new memory bank or get an existing one.
+
+        Memory banks are isolated stores - each one is like a separate "brain" for a user/agent.
+        Banks are auto-created with default settings if they don't exist.
+
+        Args:
+            bank_id: Unique identifier for the bank (e.g., 'user-123', 'agent-alpha')
+            name: Optional human-friendly name for the bank
+            mission: Optional mission describing who the agent is and what they're trying to accomplish
+        """
+        try:
+            # get_bank_profile auto-creates bank if it doesn't exist
+            profile = await memory.get_bank_profile(bank_id, request_context=RequestContext())
+
+            # Update name/mission if provided
+            if name is not None or mission is not None:
+                await memory.update_bank(
+                    bank_id,
+                    name=name,
+                    mission=mission,
+                    request_context=RequestContext(),
+                )
+                # Fetch updated profile
+                profile = await memory.get_bank_profile(bank_id, request_context=RequestContext())
+
+            # Serialize disposition if it's a Pydantic model
+            if "disposition" in profile and hasattr(profile["disposition"], "model_dump"):
+                profile["disposition"] = profile["disposition"].model_dump()
+            return json.dumps(profile, indent=2)
+        except Exception as e:
+            logger.error(f"Error creating bank: {e}", exc_info=True)
+            return f'{{"error": "{e}"}}'
 
     return mcp
 
 
 class MCPMiddleware:
-    """ASGI middleware that extracts bank_id from path and sets context."""
+    """ASGI middleware that extracts bank_id from header or path and sets context.
+
+    Bank ID can be provided via:
+    1. X-Bank-Id header (recommended for Claude Code)
+    2. URL path: /mcp/{bank_id}/
+    3. Environment variable HINDSIGHT_MCP_BANK_ID (fallback default)
+
+    For Claude Code, configure with:
+        claude mcp add --transport http hindsight http://localhost:8888/mcp \\
+            --header "X-Bank-Id: my-bank"
+    """
 
     def __init__(self, app, memory: MemoryEngine):
         self.app = app
         self.memory = memory
         self.mcp_server = create_mcp_server(memory)
-        self.mcp_app = self.mcp_server.http_app()
+        self.mcp_app = self.mcp_server.http_app(path="/")
+        # Expose the lifespan for the parent app to chain
+        self.lifespan = self.mcp_app.lifespan_handler if hasattr(self.mcp_app, "lifespan_handler") else None
+
+    def _get_header(self, scope: dict, name: str) -> str | None:
+        """Extract a header value from ASGI scope."""
+        name_lower = name.lower().encode()
+        for header_name, header_value in scope.get("headers", []):
+            if header_name.lower() == name_lower:
+                return header_value.decode()
+        return None
 
     async def __call__(self, scope, receive, send):
         if scope["type"] != "http":
@@ -139,32 +288,39 @@ class MCPMiddleware:
         # Also handle case where mount path wasn't stripped (e.g., /mcp/...)
         if path.startswith("/mcp/"):
             path = path[4:]  # Remove /mcp prefix
+        elif path == "/mcp":
+            path = "/"
 
-        # Extract bank_id from path: /{bank_id}/ or /{bank_id}
-        # http_app expects requests at /
-        if not path.startswith("/") or len(path) <= 1:
-            # No bank_id in path - return error
-            await self._send_error(send, 400, "bank_id required in path: /mcp/{bank_id}/")
-            return
+        # Try to get bank_id from header first (for Claude Code compatibility)
+        bank_id = self._get_header(scope, "X-Bank-Id")
 
-        # Extract bank_id from first path segment
-        parts = path[1:].split("/", 1)
-        if not parts[0]:
-            await self._send_error(send, 400, "bank_id required in path: /mcp/{bank_id}/")
-            return
+        # MCP endpoint paths that should not be treated as bank_ids
+        MCP_ENDPOINTS = {"sse", "messages"}
 
-        bank_id = parts[0]
-        new_path = "/" + parts[1] if len(parts) > 1 else "/"
+        # If no header, try to extract from path: /{bank_id}/...
+        new_path = path
+        if not bank_id and path.startswith("/") and len(path) > 1:
+            parts = path[1:].split("/", 1)
+            # Don't treat MCP endpoints as bank_ids
+            if parts[0] and parts[0] not in MCP_ENDPOINTS:
+                # First segment looks like a bank_id
+                bank_id = parts[0]
+                new_path = "/" + parts[1] if len(parts) > 1 else "/"
+
+        # Fall back to default bank_id
+        if not bank_id:
+            bank_id = DEFAULT_BANK_ID
+            logger.debug(f"Using default bank_id: {bank_id}")
 
         # Set bank_id context
         token = _current_bank_id.set(bank_id)
         try:
             new_scope = scope.copy()
             new_scope["path"] = new_path
+            # Clear root_path since we're passing directly to the app
+            new_scope["root_path"] = ""
 
-            # Wrap send to rewrite the SSE endpoint URL to include bank_id
-            # The SSE app sends "event: endpoint\ndata: /messages\n" but we need
-            # the client to POST to /{bank_id}/messages instead
+            # Wrap send to rewrite the SSE endpoint URL to include bank_id if using path-based routing
             async def send_wrapper(message):
                 if message["type"] == "http.response.body":
                     body = message.get("body", b"")
@@ -200,9 +356,10 @@ def create_mcp_app(memory: MemoryEngine):
     """
     Create an ASGI app that handles MCP requests.
 
-    URL pattern: /mcp/{bank_id}/
-
-    The bank_id is extracted from the URL path and made available to tools.
+    Bank ID can be provided via:
+    1. X-Bank-Id header: claude mcp add --transport http hindsight http://localhost:8888/mcp --header "X-Bank-Id: my-bank"
+    2. URL path: /mcp/{bank_id}/
+    3. Environment variable HINDSIGHT_MCP_BANK_ID (fallback, default: "default")
 
     Args:
         memory: MemoryEngine instance

hindsight-api/hindsight_api/config.py

@@ -8,6 +8,11 @@ import logging
 import os
 from dataclasses import dataclass
 
+from dotenv import find_dotenv, load_dotenv
+
+# Load .env file, searching current and parent directories (overrides existing env vars)
+load_dotenv(find_dotenv(usecwd=True), override=True)
+
 logger = logging.getLogger(__name__)
 
 # Environment variable names
@@ -16,40 +21,164 @@ ENV_LLM_PROVIDER = "HINDSIGHT_API_LLM_PROVIDER"
 ENV_LLM_API_KEY = "HINDSIGHT_API_LLM_API_KEY"
 ENV_LLM_MODEL = "HINDSIGHT_API_LLM_MODEL"
 ENV_LLM_BASE_URL = "HINDSIGHT_API_LLM_BASE_URL"
+ENV_LLM_MAX_CONCURRENT = "HINDSIGHT_API_LLM_MAX_CONCURRENT"
+ENV_LLM_TIMEOUT = "HINDSIGHT_API_LLM_TIMEOUT"
+ENV_LLM_GROQ_SERVICE_TIER = "HINDSIGHT_API_LLM_GROQ_SERVICE_TIER"
+
+# Per-operation LLM configuration (optional, falls back to global LLM config)
+ENV_RETAIN_LLM_PROVIDER = "HINDSIGHT_API_RETAIN_LLM_PROVIDER"
+ENV_RETAIN_LLM_API_KEY = "HINDSIGHT_API_RETAIN_LLM_API_KEY"
+ENV_RETAIN_LLM_MODEL = "HINDSIGHT_API_RETAIN_LLM_MODEL"
+ENV_RETAIN_LLM_BASE_URL = "HINDSIGHT_API_RETAIN_LLM_BASE_URL"
+
+ENV_REFLECT_LLM_PROVIDER = "HINDSIGHT_API_REFLECT_LLM_PROVIDER"
+ENV_REFLECT_LLM_API_KEY = "HINDSIGHT_API_REFLECT_LLM_API_KEY"
+ENV_REFLECT_LLM_MODEL = "HINDSIGHT_API_REFLECT_LLM_MODEL"
+ENV_REFLECT_LLM_BASE_URL = "HINDSIGHT_API_REFLECT_LLM_BASE_URL"
 
 ENV_EMBEDDINGS_PROVIDER = "HINDSIGHT_API_EMBEDDINGS_PROVIDER"
 ENV_EMBEDDINGS_LOCAL_MODEL = "HINDSIGHT_API_EMBEDDINGS_LOCAL_MODEL"
 ENV_EMBEDDINGS_TEI_URL = "HINDSIGHT_API_EMBEDDINGS_TEI_URL"
+ENV_EMBEDDINGS_OPENAI_API_KEY = "HINDSIGHT_API_EMBEDDINGS_OPENAI_API_KEY"
+ENV_EMBEDDINGS_OPENAI_MODEL = "HINDSIGHT_API_EMBEDDINGS_OPENAI_MODEL"
+ENV_EMBEDDINGS_OPENAI_BASE_URL = "HINDSIGHT_API_EMBEDDINGS_OPENAI_BASE_URL"
+
+ENV_COHERE_API_KEY = "HINDSIGHT_API_COHERE_API_KEY"
+ENV_EMBEDDINGS_COHERE_MODEL = "HINDSIGHT_API_EMBEDDINGS_COHERE_MODEL"
+ENV_EMBEDDINGS_COHERE_BASE_URL = "HINDSIGHT_API_EMBEDDINGS_COHERE_BASE_URL"
+ENV_RERANKER_COHERE_MODEL = "HINDSIGHT_API_RERANKER_COHERE_MODEL"
+ENV_RERANKER_COHERE_BASE_URL = "HINDSIGHT_API_RERANKER_COHERE_BASE_URL"
+
+# LiteLLM gateway configuration (for embeddings and reranker via LiteLLM proxy)
+ENV_LITELLM_API_BASE = "HINDSIGHT_API_LITELLM_API_BASE"
+ENV_LITELLM_API_KEY = "HINDSIGHT_API_LITELLM_API_KEY"
+ENV_EMBEDDINGS_LITELLM_MODEL = "HINDSIGHT_API_EMBEDDINGS_LITELLM_MODEL"
+ENV_RERANKER_LITELLM_MODEL = "HINDSIGHT_API_RERANKER_LITELLM_MODEL"
 
 ENV_RERANKER_PROVIDER = "HINDSIGHT_API_RERANKER_PROVIDER"
 ENV_RERANKER_LOCAL_MODEL = "HINDSIGHT_API_RERANKER_LOCAL_MODEL"
+ENV_RERANKER_LOCAL_MAX_CONCURRENT = "HINDSIGHT_API_RERANKER_LOCAL_MAX_CONCURRENT"
 ENV_RERANKER_TEI_URL = "HINDSIGHT_API_RERANKER_TEI_URL"
+ENV_RERANKER_TEI_BATCH_SIZE = "HINDSIGHT_API_RERANKER_TEI_BATCH_SIZE"
+ENV_RERANKER_TEI_MAX_CONCURRENT = "HINDSIGHT_API_RERANKER_TEI_MAX_CONCURRENT"
+ENV_RERANKER_MAX_CANDIDATES = "HINDSIGHT_API_RERANKER_MAX_CANDIDATES"
+ENV_RERANKER_FLASHRANK_MODEL = "HINDSIGHT_API_RERANKER_FLASHRANK_MODEL"
+ENV_RERANKER_FLASHRANK_CACHE_DIR = "HINDSIGHT_API_RERANKER_FLASHRANK_CACHE_DIR"
 
 ENV_HOST = "HINDSIGHT_API_HOST"
 ENV_PORT = "HINDSIGHT_API_PORT"
 ENV_LOG_LEVEL = "HINDSIGHT_API_LOG_LEVEL"
+ENV_WORKERS = "HINDSIGHT_API_WORKERS"
 ENV_MCP_ENABLED = "HINDSIGHT_API_MCP_ENABLED"
 ENV_GRAPH_RETRIEVER = "HINDSIGHT_API_GRAPH_RETRIEVER"
+ENV_MPFP_TOP_K_NEIGHBORS = "HINDSIGHT_API_MPFP_TOP_K_NEIGHBORS"
+ENV_RECALL_MAX_CONCURRENT = "HINDSIGHT_API_RECALL_MAX_CONCURRENT"
+ENV_RECALL_CONNECTION_BUDGET = "HINDSIGHT_API_RECALL_CONNECTION_BUDGET"
 ENV_MCP_LOCAL_BANK_ID = "HINDSIGHT_API_MCP_LOCAL_BANK_ID"
 ENV_MCP_INSTRUCTIONS = "HINDSIGHT_API_MCP_INSTRUCTIONS"
+ENV_MENTAL_MODEL_REFRESH_CONCURRENCY = "HINDSIGHT_API_MENTAL_MODEL_REFRESH_CONCURRENCY"
+
+# Observation thresholds
+ENV_OBSERVATION_MIN_FACTS = "HINDSIGHT_API_OBSERVATION_MIN_FACTS"
+ENV_OBSERVATION_TOP_ENTITIES = "HINDSIGHT_API_OBSERVATION_TOP_ENTITIES"
+
+# Retain settings
+ENV_RETAIN_MAX_COMPLETION_TOKENS = "HINDSIGHT_API_RETAIN_MAX_COMPLETION_TOKENS"
+ENV_RETAIN_CHUNK_SIZE = "HINDSIGHT_API_RETAIN_CHUNK_SIZE"
+ENV_RETAIN_EXTRACT_CAUSAL_LINKS = "HINDSIGHT_API_RETAIN_EXTRACT_CAUSAL_LINKS"
+ENV_RETAIN_EXTRACTION_MODE = "HINDSIGHT_API_RETAIN_EXTRACTION_MODE"
+ENV_RETAIN_OBSERVATIONS_ASYNC = "HINDSIGHT_API_RETAIN_OBSERVATIONS_ASYNC"
+
+# Optimization flags
+ENV_SKIP_LLM_VERIFICATION = "HINDSIGHT_API_SKIP_LLM_VERIFICATION"
+ENV_LAZY_RERANKER = "HINDSIGHT_API_LAZY_RERANKER"
+
+# Database migrations
+ENV_RUN_MIGRATIONS_ON_STARTUP = "HINDSIGHT_API_RUN_MIGRATIONS_ON_STARTUP"
+
+# Database connection pool
+ENV_DB_POOL_MIN_SIZE = "HINDSIGHT_API_DB_POOL_MIN_SIZE"
+ENV_DB_POOL_MAX_SIZE = "HINDSIGHT_API_DB_POOL_MAX_SIZE"
+ENV_DB_COMMAND_TIMEOUT = "HINDSIGHT_API_DB_COMMAND_TIMEOUT"
+ENV_DB_ACQUIRE_TIMEOUT = "HINDSIGHT_API_DB_ACQUIRE_TIMEOUT"
+
+# Background task processing
+ENV_TASK_BACKEND = "HINDSIGHT_API_TASK_BACKEND"
+ENV_TASK_BACKEND_MEMORY_BATCH_SIZE = "HINDSIGHT_API_TASK_BACKEND_MEMORY_BATCH_SIZE"
+ENV_TASK_BACKEND_MEMORY_BATCH_INTERVAL = "HINDSIGHT_API_TASK_BACKEND_MEMORY_BATCH_INTERVAL"
+
+# Reflect agent settings
+ENV_REFLECT_MAX_ITERATIONS = "HINDSIGHT_API_REFLECT_MAX_ITERATIONS"
 
 # Default values
 DEFAULT_DATABASE_URL = "pg0"
 DEFAULT_LLM_PROVIDER = "openai"
 DEFAULT_LLM_MODEL = "gpt-5-mini"
+DEFAULT_LLM_MAX_CONCURRENT = 32
+DEFAULT_LLM_TIMEOUT = 120.0  # seconds
 
 DEFAULT_EMBEDDINGS_PROVIDER = "local"
 DEFAULT_EMBEDDINGS_LOCAL_MODEL = "BAAI/bge-small-en-v1.5"
+DEFAULT_EMBEDDINGS_OPENAI_MODEL = "text-embedding-3-small"
+DEFAULT_EMBEDDING_DIMENSION = 384
 
 DEFAULT_RERANKER_PROVIDER = "local"
 DEFAULT_RERANKER_LOCAL_MODEL = "cross-encoder/ms-marco-MiniLM-L-6-v2"
+DEFAULT_RERANKER_LOCAL_MAX_CONCURRENT = 4  # Limit concurrent CPU-bound reranking to prevent thrashing
+DEFAULT_RERANKER_TEI_BATCH_SIZE = 128
+DEFAULT_RERANKER_TEI_MAX_CONCURRENT = 8
+DEFAULT_RERANKER_MAX_CANDIDATES = 300
+DEFAULT_RERANKER_FLASHRANK_MODEL = "ms-marco-MiniLM-L-12-v2"  # Best balance of speed and quality
+DEFAULT_RERANKER_FLASHRANK_CACHE_DIR = None  # Use default cache directory
+
+DEFAULT_EMBEDDINGS_COHERE_MODEL = "embed-english-v3.0"
+DEFAULT_RERANKER_COHERE_MODEL = "rerank-english-v3.0"
+
+# LiteLLM defaults
+DEFAULT_LITELLM_API_BASE = "http://localhost:4000"
+DEFAULT_EMBEDDINGS_LITELLM_MODEL = "text-embedding-3-small"
+DEFAULT_RERANKER_LITELLM_MODEL = "cohere/rerank-english-v3.0"
 
 DEFAULT_HOST = "0.0.0.0"
 DEFAULT_PORT = 8888
 DEFAULT_LOG_LEVEL = "info"
+DEFAULT_WORKERS = 1
 DEFAULT_MCP_ENABLED = True
-DEFAULT_GRAPH_RETRIEVER = "bfs"  # Options: "bfs", "mpfp"
+DEFAULT_GRAPH_RETRIEVER = "link_expansion"  # Options: "link_expansion", "mpfp", "bfs"
+DEFAULT_MPFP_TOP_K_NEIGHBORS = 20  # Fan-out limit per node in MPFP graph traversal
+DEFAULT_RECALL_MAX_CONCURRENT = 32  # Max concurrent recall operations per worker
+DEFAULT_RECALL_CONNECTION_BUDGET = 4  # Max concurrent DB connections per recall operation
 DEFAULT_MCP_LOCAL_BANK_ID = "mcp"
+DEFAULT_MENTAL_MODEL_REFRESH_CONCURRENCY = 8  # Max concurrent mental model refreshes
+
+# Observation thresholds
+DEFAULT_OBSERVATION_MIN_FACTS = 5  # Min facts required to generate entity observations
+DEFAULT_OBSERVATION_TOP_ENTITIES = 5  # Max entities to process per retain batch
+
+# Retain settings
+DEFAULT_RETAIN_MAX_COMPLETION_TOKENS = 64000  # Max tokens for fact extraction LLM call
+DEFAULT_RETAIN_CHUNK_SIZE = 3000  # Max chars per chunk for fact extraction
+DEFAULT_RETAIN_EXTRACT_CAUSAL_LINKS = True  # Extract causal links between facts
+DEFAULT_RETAIN_EXTRACTION_MODE = "concise"  # Extraction mode: "concise" or "verbose"
+RETAIN_EXTRACTION_MODES = ("concise", "verbose")  # Allowed extraction modes
+DEFAULT_RETAIN_OBSERVATIONS_ASYNC = False  # Run observation generation async (after retain completes)
+
+# Database migrations
+DEFAULT_RUN_MIGRATIONS_ON_STARTUP = True
+
+# Database connection pool
+DEFAULT_DB_POOL_MIN_SIZE = 5
+DEFAULT_DB_POOL_MAX_SIZE = 100
+DEFAULT_DB_COMMAND_TIMEOUT = 60  # seconds
+DEFAULT_DB_ACQUIRE_TIMEOUT = 30  # seconds
+
+# Background task processing
+DEFAULT_TASK_BACKEND = "memory"  # Options: "memory", "noop"
+DEFAULT_TASK_BACKEND_MEMORY_BATCH_SIZE = 10
+DEFAULT_TASK_BACKEND_MEMORY_BATCH_INTERVAL = 1.0  # seconds
+
+# Reflect agent settings
+DEFAULT_REFLECT_MAX_ITERATIONS = 10  # Max tool call iterations before forcing response
 
 # Default MCP tool descriptions (can be customized via env vars)
 DEFAULT_MCP_RETAIN_DESCRIPTION = """Store important information to long-term memory.
@@ -71,8 +200,20 @@ Use this tool PROACTIVELY to:
 - Remember user's goals and context
 - Personalize responses based on past interactions"""
 
-# Required embedding dimension for database schema
-EMBEDDING_DIMENSION = 384
+# Default embedding dimension (used by initial migration, adjusted at runtime)
+EMBEDDING_DIMENSION = DEFAULT_EMBEDDING_DIMENSION
+
+
+def _validate_extraction_mode(mode: str) -> str:
+    """Validate and normalize extraction mode."""
+    mode_lower = mode.lower()
+    if mode_lower not in RETAIN_EXTRACTION_MODES:
+        logger.warning(
+            f"Invalid extraction mode '{mode}', must be one of {RETAIN_EXTRACTION_MODES}. "
+            f"Defaulting to '{DEFAULT_RETAIN_EXTRACTION_MODE}'."
+        )
+        return DEFAULT_RETAIN_EXTRACTION_MODE
+    return mode_lower
 
 
 @dataclass
@@ -82,21 +223,40 @@ class HindsightConfig:
     # Database
     database_url: str
 
-    # LLM
+    # LLM (default, used as fallback for per-operation config)
     llm_provider: str
     llm_api_key: str | None
     llm_model: str
     llm_base_url: str | None
+    llm_max_concurrent: int
+    llm_timeout: float
+
+    # Per-operation LLM configuration (None = use default LLM config)
+    retain_llm_provider: str | None
+    retain_llm_api_key: str | None
+    retain_llm_model: str | None
+    retain_llm_base_url: str | None
+
+    reflect_llm_provider: str | None
+    reflect_llm_api_key: str | None
+    reflect_llm_model: str | None
+    reflect_llm_base_url: str | None
 
     # Embeddings
     embeddings_provider: str
     embeddings_local_model: str
     embeddings_tei_url: str | None
+    embeddings_openai_base_url: str | None
+    embeddings_cohere_base_url: str | None
 
     # Reranker
     reranker_provider: str
     reranker_local_model: str
     reranker_tei_url: str | None
+    reranker_tei_batch_size: int
+    reranker_tei_max_concurrent: int
+    reranker_max_candidates: int
+    reranker_cohere_base_url: str | None
 
     # Server
     host: str
@@ -106,6 +266,42 @@ class HindsightConfig:
 
     # Recall
     graph_retriever: str
+    mpfp_top_k_neighbors: int
+    recall_max_concurrent: int
+    recall_connection_budget: int
+    mental_model_refresh_concurrency: int
+
+    # Observation thresholds
+    observation_min_facts: int
+    observation_top_entities: int
+
+    # Retain settings
+    retain_max_completion_tokens: int
+    retain_chunk_size: int
+    retain_extract_causal_links: bool
+    retain_extraction_mode: str
+    retain_observations_async: bool
+
+    # Optimization flags
+    skip_llm_verification: bool
+    lazy_reranker: bool
+
+    # Database migrations
+    run_migrations_on_startup: bool
+
+    # Database connection pool
+    db_pool_min_size: int
+    db_pool_max_size: int
+    db_command_timeout: int
+    db_acquire_timeout: int
+
+    # Background task processing
+    task_backend: str
+    task_backend_memory_batch_size: int
+    task_backend_memory_batch_interval: float
+
+    # Reflect agent settings
+    reflect_max_iterations: int
 
     @classmethod
     def from_env(cls) -> "HindsightConfig":
@@ -118,14 +314,33 @@ class HindsightConfig:
             llm_api_key=os.getenv(ENV_LLM_API_KEY),
             llm_model=os.getenv(ENV_LLM_MODEL, DEFAULT_LLM_MODEL),
             llm_base_url=os.getenv(ENV_LLM_BASE_URL) or None,
+            llm_max_concurrent=int(os.getenv(ENV_LLM_MAX_CONCURRENT, str(DEFAULT_LLM_MAX_CONCURRENT))),
+            llm_timeout=float(os.getenv(ENV_LLM_TIMEOUT, str(DEFAULT_LLM_TIMEOUT))),
+            # Per-operation LLM config (None = use default)
+            retain_llm_provider=os.getenv(ENV_RETAIN_LLM_PROVIDER) or None,
+            retain_llm_api_key=os.getenv(ENV_RETAIN_LLM_API_KEY) or None,
+            retain_llm_model=os.getenv(ENV_RETAIN_LLM_MODEL) or None,
+            retain_llm_base_url=os.getenv(ENV_RETAIN_LLM_BASE_URL) or None,
+            reflect_llm_provider=os.getenv(ENV_REFLECT_LLM_PROVIDER) or None,
+            reflect_llm_api_key=os.getenv(ENV_REFLECT_LLM_API_KEY) or None,
+            reflect_llm_model=os.getenv(ENV_REFLECT_LLM_MODEL) or None,
+            reflect_llm_base_url=os.getenv(ENV_REFLECT_LLM_BASE_URL) or None,
             # Embeddings
             embeddings_provider=os.getenv(ENV_EMBEDDINGS_PROVIDER, DEFAULT_EMBEDDINGS_PROVIDER),
             embeddings_local_model=os.getenv(ENV_EMBEDDINGS_LOCAL_MODEL, DEFAULT_EMBEDDINGS_LOCAL_MODEL),
             embeddings_tei_url=os.getenv(ENV_EMBEDDINGS_TEI_URL),
+            embeddings_openai_base_url=os.getenv(ENV_EMBEDDINGS_OPENAI_BASE_URL) or None,
+            embeddings_cohere_base_url=os.getenv(ENV_EMBEDDINGS_COHERE_BASE_URL) or None,
             # Reranker
             reranker_provider=os.getenv(ENV_RERANKER_PROVIDER, DEFAULT_RERANKER_PROVIDER),
             reranker_local_model=os.getenv(ENV_RERANKER_LOCAL_MODEL, DEFAULT_RERANKER_LOCAL_MODEL),
             reranker_tei_url=os.getenv(ENV_RERANKER_TEI_URL),
+            reranker_tei_batch_size=int(os.getenv(ENV_RERANKER_TEI_BATCH_SIZE, str(DEFAULT_RERANKER_TEI_BATCH_SIZE))),
+            reranker_tei_max_concurrent=int(
+                os.getenv(ENV_RERANKER_TEI_MAX_CONCURRENT, str(DEFAULT_RERANKER_TEI_MAX_CONCURRENT))
+            ),
+            reranker_max_candidates=int(os.getenv(ENV_RERANKER_MAX_CANDIDATES, str(DEFAULT_RERANKER_MAX_CANDIDATES))),
+            reranker_cohere_base_url=os.getenv(ENV_RERANKER_COHERE_BASE_URL) or None,
             # Server
             host=os.getenv(ENV_HOST, DEFAULT_HOST),
             port=int(os.getenv(ENV_PORT, DEFAULT_PORT)),
@@ -133,6 +348,55 @@ class HindsightConfig:
             mcp_enabled=os.getenv(ENV_MCP_ENABLED, str(DEFAULT_MCP_ENABLED)).lower() == "true",
             # Recall
             graph_retriever=os.getenv(ENV_GRAPH_RETRIEVER, DEFAULT_GRAPH_RETRIEVER),
+            mpfp_top_k_neighbors=int(os.getenv(ENV_MPFP_TOP_K_NEIGHBORS, str(DEFAULT_MPFP_TOP_K_NEIGHBORS))),
+            recall_max_concurrent=int(os.getenv(ENV_RECALL_MAX_CONCURRENT, str(DEFAULT_RECALL_MAX_CONCURRENT))),
+            recall_connection_budget=int(
+                os.getenv(ENV_RECALL_CONNECTION_BUDGET, str(DEFAULT_RECALL_CONNECTION_BUDGET))
+            ),
+            mental_model_refresh_concurrency=int(
+                os.getenv(ENV_MENTAL_MODEL_REFRESH_CONCURRENCY, str(DEFAULT_MENTAL_MODEL_REFRESH_CONCURRENCY))
+            ),
+            # Optimization flags
+            skip_llm_verification=os.getenv(ENV_SKIP_LLM_VERIFICATION, "false").lower() == "true",
+            lazy_reranker=os.getenv(ENV_LAZY_RERANKER, "false").lower() == "true",
+            # Observation thresholds
+            observation_min_facts=int(os.getenv(ENV_OBSERVATION_MIN_FACTS, str(DEFAULT_OBSERVATION_MIN_FACTS))),
+            observation_top_entities=int(
+                os.getenv(ENV_OBSERVATION_TOP_ENTITIES, str(DEFAULT_OBSERVATION_TOP_ENTITIES))
+            ),
+            # Retain settings
+            retain_max_completion_tokens=int(
+                os.getenv(ENV_RETAIN_MAX_COMPLETION_TOKENS, str(DEFAULT_RETAIN_MAX_COMPLETION_TOKENS))
+            ),
+            retain_chunk_size=int(os.getenv(ENV_RETAIN_CHUNK_SIZE, str(DEFAULT_RETAIN_CHUNK_SIZE))),
+            retain_extract_causal_links=os.getenv(
+                ENV_RETAIN_EXTRACT_CAUSAL_LINKS, str(DEFAULT_RETAIN_EXTRACT_CAUSAL_LINKS)
+            ).lower()
+            == "true",
+            retain_extraction_mode=_validate_extraction_mode(
+                os.getenv(ENV_RETAIN_EXTRACTION_MODE, DEFAULT_RETAIN_EXTRACTION_MODE)
+            ),
+            retain_observations_async=os.getenv(
+                ENV_RETAIN_OBSERVATIONS_ASYNC, str(DEFAULT_RETAIN_OBSERVATIONS_ASYNC)
+            ).lower()
+            == "true",
+            # Database migrations
+            run_migrations_on_startup=os.getenv(ENV_RUN_MIGRATIONS_ON_STARTUP, "true").lower() == "true",
+            # Database connection pool
+            db_pool_min_size=int(os.getenv(ENV_DB_POOL_MIN_SIZE, str(DEFAULT_DB_POOL_MIN_SIZE))),
+            db_pool_max_size=int(os.getenv(ENV_DB_POOL_MAX_SIZE, str(DEFAULT_DB_POOL_MAX_SIZE))),
+            db_command_timeout=int(os.getenv(ENV_DB_COMMAND_TIMEOUT, str(DEFAULT_DB_COMMAND_TIMEOUT))),
+            db_acquire_timeout=int(os.getenv(ENV_DB_ACQUIRE_TIMEOUT, str(DEFAULT_DB_ACQUIRE_TIMEOUT))),
+            # Background task processing
+            task_backend=os.getenv(ENV_TASK_BACKEND, DEFAULT_TASK_BACKEND),
+            task_backend_memory_batch_size=int(
+                os.getenv(ENV_TASK_BACKEND_MEMORY_BATCH_SIZE, str(DEFAULT_TASK_BACKEND_MEMORY_BATCH_SIZE))
+            ),
+            task_backend_memory_batch_interval=float(
+                os.getenv(ENV_TASK_BACKEND_MEMORY_BATCH_INTERVAL, str(DEFAULT_TASK_BACKEND_MEMORY_BATCH_INTERVAL))
+            ),
+            # Reflect agent settings
+            reflect_max_iterations=int(os.getenv(ENV_REFLECT_MAX_ITERATIONS, str(DEFAULT_REFLECT_MAX_ITERATIONS))),
         )
 
     def get_llm_base_url(self) -> str:
@@ -145,6 +409,8 @@ class HindsightConfig:
             return "https://api.groq.com/openai/v1"
         elif provider == "ollama":
             return "http://localhost:11434/v1"
+        elif provider == "lmstudio":
+            return "http://localhost:1234/v1"
         else:
             return ""
 
@@ -172,11 +438,32 @@ class HindsightConfig:
         """Log the current configuration (without sensitive values)."""
         logger.info(f"Database: {self.database_url}")
         logger.info(f"LLM: provider={self.llm_provider}, model={self.llm_model}")
+        if self.retain_llm_provider or self.retain_llm_model:
+            retain_provider = self.retain_llm_provider or self.llm_provider
+            retain_model = self.retain_llm_model or self.llm_model
+            logger.info(f"LLM (retain): provider={retain_provider}, model={retain_model}")
+        if self.reflect_llm_provider or self.reflect_llm_model:
+            reflect_provider = self.reflect_llm_provider or self.llm_provider
+            reflect_model = self.reflect_llm_model or self.llm_model
+            logger.info(f"LLM (reflect): provider={reflect_provider}, model={reflect_model}")
         logger.info(f"Embeddings: provider={self.embeddings_provider}")
         logger.info(f"Reranker: provider={self.reranker_provider}")
         logger.info(f"Graph retriever: {self.graph_retriever}")
 
 
+# Cached config instance
+_config_cache: HindsightConfig | None = None
+
+
 def get_config() -> HindsightConfig:
-    """Get the current configuration from environment variables."""
-    return HindsightConfig.from_env()
+    """Get the cached configuration, loading from environment on first call."""
+    global _config_cache
+    if _config_cache is None:
+        _config_cache = HindsightConfig.from_env()
+    return _config_cache
+
+
+def clear_config_cache() -> None:
+    """Clear the config cache. Useful for testing or reloading config."""
+    global _config_cache
+    _config_cache = None

hindsight-api/hindsight_api/daemon.py

@@ -0,0 +1,204 @@
+"""
+Daemon mode support for Hindsight API.
+
+Provides idle timeout and lockfile management for running as a background daemon.
+"""
+
+import asyncio
+import fcntl
+import logging
+import os
+import sys
+import time
+from pathlib import Path
+
+logger = logging.getLogger(__name__)
+
+# Default daemon configuration
+DEFAULT_DAEMON_PORT = 8889
+DEFAULT_IDLE_TIMEOUT = 0  # 0 = no auto-exit (hindsight-embed passes its own timeout)
+LOCKFILE_PATH = Path.home() / ".hindsight" / "daemon.lock"
+DAEMON_LOG_PATH = Path.home() / ".hindsight" / "daemon.log"
+
+
+class IdleTimeoutMiddleware:
+    """ASGI middleware that tracks activity and exits after idle timeout."""
+
+    def __init__(self, app, idle_timeout: int = DEFAULT_IDLE_TIMEOUT):
+        self.app = app
+        self.idle_timeout = idle_timeout
+        self.last_activity = time.time()
+        self._checker_task = None
+
+    async def __call__(self, scope, receive, send):
+        # Update activity timestamp on each request
+        self.last_activity = time.time()
+        await self.app(scope, receive, send)
+
+    def start_idle_checker(self):
+        """Start the background task that checks for idle timeout."""
+        self._checker_task = asyncio.create_task(self._check_idle())
+
+    async def _check_idle(self):
+        """Background task that exits the process after idle timeout."""
+        # If idle_timeout is 0, don't auto-exit
+        if self.idle_timeout <= 0:
+            return
+
+        while True:
+            await asyncio.sleep(30)  # Check every 30 seconds
+            idle_time = time.time() - self.last_activity
+            if idle_time > self.idle_timeout:
+                logger.info(f"Idle timeout reached ({self.idle_timeout}s), shutting down daemon")
+                # Give a moment for any in-flight requests
+                await asyncio.sleep(1)
+                os._exit(0)
+
+
+class DaemonLock:
+    """
+    File-based lock to prevent multiple daemon instances.
+
+    Uses fcntl.flock for atomic locking on Unix systems.
+    """
+
+    def __init__(self, lockfile: Path = LOCKFILE_PATH):
+        self.lockfile = lockfile
+        self._fd = None
+
+    def acquire(self) -> bool:
+        """
+        Try to acquire the daemon lock.
+
+        Returns True if lock acquired, False if another daemon is running.
+        """
+        self.lockfile.parent.mkdir(parents=True, exist_ok=True)
+
+        try:
+            self._fd = open(self.lockfile, "w")
+            fcntl.flock(self._fd.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
+            # Write PID for debugging
+            self._fd.write(str(os.getpid()))
+            self._fd.flush()
+            return True
+        except (IOError, OSError):
+            # Lock is held by another process
+            if self._fd:
+                self._fd.close()
+                self._fd = None
+            return False
+
+    def release(self):
+        """Release the daemon lock."""
+        if self._fd:
+            try:
+                fcntl.flock(self._fd.fileno(), fcntl.LOCK_UN)
+                self._fd.close()
+            except Exception:
+                pass
+            finally:
+                self._fd = None
+                # Remove lockfile
+                try:
+                    self.lockfile.unlink()
+                except Exception:
+                    pass
+
+    def is_locked(self) -> bool:
+        """Check if the lock is held by another process."""
+        if not self.lockfile.exists():
+            return False
+
+        try:
+            fd = open(self.lockfile, "r")
+            fcntl.flock(fd.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
+            # We got the lock, so no one else has it
+            fcntl.flock(fd.fileno(), fcntl.LOCK_UN)
+            fd.close()
+            return False
+        except (IOError, OSError):
+            return True
+
+    def get_pid(self) -> int | None:
+        """Get the PID of the daemon holding the lock."""
+        if not self.lockfile.exists():
+            return None
+        try:
+            with open(self.lockfile, "r") as f:
+                return int(f.read().strip())
+        except (ValueError, IOError):
+            return None
+
+
+def daemonize():
+    """
+    Fork the current process into a background daemon.
+
+    Uses double-fork technique to properly detach from terminal.
+    """
+    # First fork
+    pid = os.fork()
+    if pid > 0:
+        # Parent exits
+        sys.exit(0)
+
+    # Create new session
+    os.setsid()
+
+    # Second fork to prevent zombie processes
+    pid = os.fork()
+    if pid > 0:
+        sys.exit(0)
+
+    # Redirect standard file descriptors to log file
+    DAEMON_LOG_PATH.parent.mkdir(parents=True, exist_ok=True)
+
+    sys.stdout.flush()
+    sys.stderr.flush()
+
+    # Redirect stdin to /dev/null
+    with open("/dev/null", "r") as devnull:
+        os.dup2(devnull.fileno(), sys.stdin.fileno())
+
+    # Redirect stdout/stderr to log file
+    log_fd = open(DAEMON_LOG_PATH, "a")
+    os.dup2(log_fd.fileno(), sys.stdout.fileno())
+    os.dup2(log_fd.fileno(), sys.stderr.fileno())
+
+
+def check_daemon_running(port: int = DEFAULT_DAEMON_PORT) -> bool:
+    """Check if a daemon is running and responsive on the given port."""
+    import socket
+
+    try:
+        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        sock.settimeout(1)
+        result = sock.connect_ex(("127.0.0.1", port))
+        sock.close()
+        return result == 0
+    except Exception:
+        return False
+
+
+def stop_daemon(port: int = DEFAULT_DAEMON_PORT) -> bool:
+    """Stop a running daemon by sending SIGTERM to the process."""
+    lock = DaemonLock()
+    pid = lock.get_pid()
+
+    if pid is None:
+        return False
+
+    try:
+        import signal
+
+        os.kill(pid, signal.SIGTERM)
+        # Wait for process to exit
+        for _ in range(50):  # Wait up to 5 seconds
+            time.sleep(0.1)
+            try:
+                os.kill(pid, 0)  # Check if process exists
+            except OSError:
+                return True  # Process exited
+        return False
+    except OSError:
+        return False

hindsight-api/hindsight_api/engine/__init__.py

@@ -11,7 +11,13 @@ from .cross_encoder import CrossEncoderModel, LocalSTCrossEncoder, RemoteTEICros
 from .db_utils import acquire_with_retry
 from .embeddings import Embeddings, LocalSTEmbeddings, RemoteTEIEmbeddings
 from .llm_wrapper import LLMConfig
-from .memory_engine import MemoryEngine
+from .memory_engine import (
+    MemoryEngine,
+    UnqualifiedTableError,
+    fq_table,
+    get_current_schema,
+    validate_sql_schema,
+)
 from .response_models import MemoryFact, RecallResult, ReflectResult
 from .search.trace import (
     EntryPoint,
@@ -49,4 +55,9 @@ __all__ = [
     "RecallResult",
     "ReflectResult",
     "MemoryFact",
+    # Schema safety utilities
+    "fq_table",
+    "get_current_schema",
+    "validate_sql_schema",
+    "UnqualifiedTableError",
 ]

hindsight-api/hindsight_api/engine/cross_encoder.py

@@ -6,17 +6,38 @@ Provides an interface for reranking with different backends.
 Configuration via environment variables - see hindsight_api.config for all env var names.
 """
 
+import asyncio
 import logging
 import os
 from abc import ABC, abstractmethod
+from concurrent.futures import ThreadPoolExecutor
 
 import httpx
 
 from ..config import (
+    DEFAULT_LITELLM_API_BASE,
+    DEFAULT_RERANKER_COHERE_MODEL,
+    DEFAULT_RERANKER_FLASHRANK_CACHE_DIR,
+    DEFAULT_RERANKER_FLASHRANK_MODEL,
+    DEFAULT_RERANKER_LITELLM_MODEL,
+    DEFAULT_RERANKER_LOCAL_MAX_CONCURRENT,
     DEFAULT_RERANKER_LOCAL_MODEL,
     DEFAULT_RERANKER_PROVIDER,
+    DEFAULT_RERANKER_TEI_BATCH_SIZE,
+    DEFAULT_RERANKER_TEI_MAX_CONCURRENT,
+    ENV_COHERE_API_KEY,
+    ENV_LITELLM_API_BASE,
+    ENV_LITELLM_API_KEY,
+    ENV_RERANKER_COHERE_BASE_URL,
+    ENV_RERANKER_COHERE_MODEL,
+    ENV_RERANKER_FLASHRANK_CACHE_DIR,
+    ENV_RERANKER_FLASHRANK_MODEL,
+    ENV_RERANKER_LITELLM_MODEL,
+    ENV_RERANKER_LOCAL_MAX_CONCURRENT,
     ENV_RERANKER_LOCAL_MODEL,
     ENV_RERANKER_PROVIDER,
+    ENV_RERANKER_TEI_BATCH_SIZE,
+    ENV_RERANKER_TEI_MAX_CONCURRENT,
     ENV_RERANKER_TEI_URL,
 )
 
@@ -47,7 +68,7 @@ class CrossEncoderModel(ABC):
         pass
 
     @abstractmethod
-    def predict(self, pairs: list[tuple[str, str]]) -> list[float]:
+    async def predict(self, pairs: list[tuple[str, str]]) -> list[float]:
         """
         Score query-document pairs for relevance.
 
@@ -70,25 +91,34 @@ class LocalSTCrossEncoder(CrossEncoderModel):
     - Fast inference (~80ms for 100 pairs on CPU)
     - Small model (80MB)
     - Trained for passage re-ranking
+
+    Uses a dedicated thread pool to limit concurrent CPU-bound work.
     """
 
-    def __init__(self, model_name: str | None = None):
+    # Shared executor across all instances (one model loaded anyway)
+    _executor: ThreadPoolExecutor | None = None
+    _max_concurrent: int = 4  # Limit concurrent CPU-bound reranking calls
+
+    def __init__(self, model_name: str | None = None, max_concurrent: int = 4):
         """
         Initialize local SentenceTransformers cross-encoder.
 
         Args:
             model_name: Name of the CrossEncoder model to use.
                        Default: cross-encoder/ms-marco-MiniLM-L-6-v2
+            max_concurrent: Maximum concurrent reranking calls (default: 2).
+                           Higher values may cause CPU thrashing under load.
         """
         self.model_name = model_name or DEFAULT_RERANKER_LOCAL_MODEL
         self._model = None
+        LocalSTCrossEncoder._max_concurrent = max_concurrent
 
     @property
     def provider_name(self) -> str:
         return "local"
 
     async def initialize(self) -> None:
-        """Load the cross-encoder model."""
+        """Load the cross-encoder model and initialize the executor."""
         if self._model is not None:
             return
 
@@ -100,14 +130,30 @@ class LocalSTCrossEncoder(CrossEncoderModel):
                 "Install it with: pip install sentence-transformers"
             )
 
+        # Note: We use CPU even when GPU/MPS is available because:
+        # 1. The reranker model (MiniLM) is tiny (~22M params)
+        # 2. Batch sizes are small (~100-200 pairs)
+        # 3. Data transfer overhead to GPU outweighs compute benefit
+        # 4. CPU inference is actually faster for this workload
         logger.info(f"Reranker: initializing local provider with model {self.model_name}")
         self._model = CrossEncoder(self.model_name)
-        logger.info("Reranker: local provider initialized")
 
-    def predict(self, pairs: list[tuple[str, str]]) -> list[float]:
+        # Initialize shared executor (limited workers naturally limits concurrency)
+        if LocalSTCrossEncoder._executor is None:
+            LocalSTCrossEncoder._executor = ThreadPoolExecutor(
+                max_workers=LocalSTCrossEncoder._max_concurrent,
+                thread_name_prefix="reranker",
+            )
+            logger.info(f"Reranker: local provider initialized (max_concurrent={LocalSTCrossEncoder._max_concurrent})")
+        else:
+            logger.info("Reranker: local provider initialized (using existing executor)")
+
+    async def predict(self, pairs: list[tuple[str, str]]) -> list[float]:
         """
         Score query-document pairs for relevance.
 
+        Uses a dedicated thread pool with limited workers to prevent CPU thrashing.
+
         Args:
             pairs: List of (query, document) tuples to score
 
@@ -116,7 +162,13 @@ class LocalSTCrossEncoder(CrossEncoderModel):
         """
         if self._model is None:
             raise RuntimeError("Reranker not initialized. Call initialize() first.")
-        scores = self._model.predict(pairs, show_progress_bar=False)
+
+        # Use dedicated executor - limited workers naturally limits concurrency
+        loop = asyncio.get_event_loop()
+        scores = await loop.run_in_executor(
+            LocalSTCrossEncoder._executor,
+            lambda: self._model.predict(pairs, show_progress_bar=False),
+        )
         return scores.tolist() if hasattr(scores, "tolist") else list(scores)
 
 
@@ -128,13 +180,21 @@ class RemoteTEICrossEncoder(CrossEncoderModel):
     See: https://github.com/huggingface/text-embeddings-inference
 
     Note: The TEI server must be running a cross-encoder/reranker model.
+
+    Requests are made in parallel with configurable batch size and max concurrency (backpressure).
+    Uses a GLOBAL semaphore to limit concurrent requests across ALL recall operations.
     """
 
+    # Global semaphore shared across all instances and calls to prevent thundering herd
+    _global_semaphore: asyncio.Semaphore | None = None
+    _global_max_concurrent: int = DEFAULT_RERANKER_TEI_MAX_CONCURRENT
+
     def __init__(
         self,
         base_url: str,
         timeout: float = 30.0,
-        batch_size: int = 32,
+        batch_size: int = DEFAULT_RERANKER_TEI_BATCH_SIZE,
+        max_concurrent: int = DEFAULT_RERANKER_TEI_MAX_CONCURRENT,
         max_retries: int = 3,
         retry_delay: float = 0.5,
     ):
@@ -144,80 +204,246 @@ class RemoteTEICrossEncoder(CrossEncoderModel):
         Args:
             base_url: Base URL of the TEI server (e.g., "http://localhost:8080")
             timeout: Request timeout in seconds (default: 30.0)
-            batch_size: Maximum batch size for rerank requests (default: 32)
+            batch_size: Maximum batch size for rerank requests (default: 128)
+            max_concurrent: Maximum concurrent requests for backpressure (default: 8).
+                           This is a GLOBAL limit across all parallel recall operations.
             max_retries: Maximum number of retries for failed requests (default: 3)
             retry_delay: Initial delay between retries in seconds, doubles each retry (default: 0.5)
         """
         self.base_url = base_url.rstrip("/")
         self.timeout = timeout
         self.batch_size = batch_size
+        self.max_concurrent = max_concurrent
         self.max_retries = max_retries
         self.retry_delay = retry_delay
-        self._client: httpx.Client | None = None
+        self._async_client: httpx.AsyncClient | None = None
         self._model_id: str | None = None
 
+        # Update global semaphore if max_concurrent changed
+        if (
+            RemoteTEICrossEncoder._global_semaphore is None
+            or RemoteTEICrossEncoder._global_max_concurrent != max_concurrent
+        ):
+            RemoteTEICrossEncoder._global_max_concurrent = max_concurrent
+            RemoteTEICrossEncoder._global_semaphore = asyncio.Semaphore(max_concurrent)
+
     @property
     def provider_name(self) -> str:
         return "tei"
 
-    def _request_with_retry(self, method: str, url: str, **kwargs) -> httpx.Response:
-        """Make an HTTP request with automatic retries on transient errors."""
-        import time
-
+    async def _async_request_with_retry(
+        self,
+        client: httpx.AsyncClient,
+        semaphore: asyncio.Semaphore,
+        method: str,
+        url: str,
+        **kwargs,
+    ) -> httpx.Response:
+        """Make an async HTTP request with automatic retries on transient errors and semaphore for backpressure."""
         last_error = None
         delay = self.retry_delay
 
-        for attempt in range(self.max_retries + 1):
-            try:
-                if method == "GET":
-                    response = self._client.get(url, **kwargs)
-                else:
-                    response = self._client.post(url, **kwargs)
-                response.raise_for_status()
-                return response
-            except (httpx.ConnectError, httpx.ReadTimeout, httpx.WriteTimeout) as e:
-                last_error = e
-                if attempt < self.max_retries:
-                    logger.warning(
-                        f"TEI request failed (attempt {attempt + 1}/{self.max_retries + 1}): {e}. Retrying in {delay}s..."
-                    )
-                    time.sleep(delay)
-                    delay *= 2  # Exponential backoff
-            except httpx.HTTPStatusError as e:
-                # Retry on 5xx server errors
-                if e.response.status_code >= 500 and attempt < self.max_retries:
+        async with semaphore:
+            for attempt in range(self.max_retries + 1):
+                try:
+                    if method == "GET":
+                        response = await client.get(url, **kwargs)
+                    else:
+                        response = await client.post(url, **kwargs)
+                    response.raise_for_status()
+                    return response
+                except (httpx.ConnectError, httpx.ReadTimeout, httpx.WriteTimeout) as e:
                     last_error = e
-                    logger.warning(
-                        f"TEI server error (attempt {attempt + 1}/{self.max_retries + 1}): {e}. Retrying in {delay}s..."
-                    )
-                    time.sleep(delay)
-                    delay *= 2
-                else:
-                    raise
+                    if attempt < self.max_retries:
+                        logger.warning(
+                            f"TEI request failed (attempt {attempt + 1}/{self.max_retries + 1}): {e}. "
+                            f"Retrying in {delay}s..."
+                        )
+                        await asyncio.sleep(delay)
+                        delay *= 2  # Exponential backoff
+                except httpx.HTTPStatusError as e:
+                    # Retry on 5xx server errors
+                    if e.response.status_code >= 500 and attempt < self.max_retries:
+                        last_error = e
+                        logger.warning(
+                            f"TEI server error (attempt {attempt + 1}/{self.max_retries + 1}): {e}. "
+                            f"Retrying in {delay}s..."
+                        )
+                        await asyncio.sleep(delay)
+                        delay *= 2
+                    else:
+                        raise
 
         raise last_error
 
     async def initialize(self) -> None:
         """Initialize the HTTP client and verify server connectivity."""
-        if self._client is not None:
+        if self._async_client is not None:
             return
 
-        logger.info(f"Reranker: initializing TEI provider at {self.base_url}")
-        self._client = httpx.Client(timeout=self.timeout)
+        logger.info(
+            f"Reranker: initializing TEI provider at {self.base_url} "
+            f"(batch_size={self.batch_size}, max_concurrent={self.max_concurrent})"
+        )
+        self._async_client = httpx.AsyncClient(timeout=self.timeout)
 
         # Verify server is reachable and get model info
+        # Use a temporary semaphore for initialization
+        init_semaphore = asyncio.Semaphore(1)
         try:
-            response = self._request_with_retry("GET", f"{self.base_url}/info")
+            response = await self._async_request_with_retry(
+                self._async_client, init_semaphore, "GET", f"{self.base_url}/info"
+            )
             info = response.json()
             self._model_id = info.get("model_id", "unknown")
             logger.info(f"Reranker: TEI provider initialized (model: {self._model_id})")
         except httpx.HTTPError as e:
+            self._async_client = None
             raise RuntimeError(f"Failed to connect to TEI server at {self.base_url}: {e}")
 
-    def predict(self, pairs: list[tuple[str, str]]) -> list[float]:
+    async def _rerank_query_group(
+        self,
+        client: httpx.AsyncClient,
+        semaphore: asyncio.Semaphore,
+        query: str,
+        texts: list[str],
+    ) -> list[tuple[int, float]]:
+        """Rerank a single query group and return list of (original_index, score) tuples."""
+        try:
+            response = await self._async_request_with_retry(
+                client,
+                semaphore,
+                "POST",
+                f"{self.base_url}/rerank",
+                json={
+                    "query": query,
+                    "texts": texts,
+                    "return_text": False,
+                },
+            )
+            results = response.json()
+            # TEI returns results sorted by score descending, with original index
+            return [(result["index"], result["score"]) for result in results]
+        except httpx.HTTPError as e:
+            raise RuntimeError(f"TEI rerank request failed: {e}")
+
+    async def _predict_async(self, pairs: list[tuple[str, str]]) -> list[float]:
+        """Async implementation of predict that runs requests in parallel with backpressure."""
+        if not pairs:
+            return []
+
+        # Group all pairs by query
+        query_groups: dict[str, list[tuple[int, str]]] = {}
+        for idx, (query, text) in enumerate(pairs):
+            if query not in query_groups:
+                query_groups[query] = []
+            query_groups[query].append((idx, text))
+
+        # Split each query group into batches
+        tasks_info: list[tuple[str, list[int], list[str]]] = []  # (query, indices, texts)
+        for query, indexed_texts in query_groups.items():
+            indices = [idx for idx, _ in indexed_texts]
+            texts = [text for _, text in indexed_texts]
+
+            # Split into batches
+            for i in range(0, len(texts), self.batch_size):
+                batch_indices = indices[i : i + self.batch_size]
+                batch_texts = texts[i : i + self.batch_size]
+                tasks_info.append((query, batch_indices, batch_texts))
+
+        # Run all requests in parallel with GLOBAL semaphore for backpressure
+        # This ensures max_concurrent is respected across ALL parallel recall operations
+        all_scores = [0.0] * len(pairs)
+        semaphore = RemoteTEICrossEncoder._global_semaphore
+
+        tasks = [
+            self._rerank_query_group(self._async_client, semaphore, query, texts) for query, _, texts in tasks_info
+        ]
+        results = await asyncio.gather(*tasks)
+
+        # Map scores back to original positions
+        for (_, indices, _), result_scores in zip(tasks_info, results):
+            for original_idx_in_batch, score in result_scores:
+                global_idx = indices[original_idx_in_batch]
+                all_scores[global_idx] = score
+
+        return all_scores
+
+    async def predict(self, pairs: list[tuple[str, str]]) -> list[float]:
         """
         Score query-document pairs using the remote TEI reranker.
 
+        Requests are made in parallel with configurable backpressure.
+
+        Args:
+            pairs: List of (query, document) tuples to score
+
+        Returns:
+            List of relevance scores
+        """
+        if self._async_client is None:
+            raise RuntimeError("Reranker not initialized. Call initialize() first.")
+
+        return await self._predict_async(pairs)
+
+
+class CohereCrossEncoder(CrossEncoderModel):
+    """
+    Cohere cross-encoder implementation using the Cohere Rerank API.
+
+    Supports rerank-english-v3.0 and rerank-multilingual-v3.0 models.
+    """
+
+    def __init__(
+        self,
+        api_key: str,
+        model: str = DEFAULT_RERANKER_COHERE_MODEL,
+        base_url: str | None = None,
+        timeout: float = 60.0,
+    ):
+        """
+        Initialize Cohere cross-encoder client.
+
+        Args:
+            api_key: Cohere API key
+            model: Cohere rerank model name (default: rerank-english-v3.0)
+            base_url: Custom base URL for Cohere-compatible API (e.g., Azure-hosted endpoint)
+            timeout: Request timeout in seconds (default: 60.0)
+        """
+        self.api_key = api_key
+        self.model = model
+        self.base_url = base_url
+        self.timeout = timeout
+        self._client = None
+
+    @property
+    def provider_name(self) -> str:
+        return "cohere"
+
+    async def initialize(self) -> None:
+        """Initialize the Cohere client."""
+        if self._client is not None:
+            return
+
+        try:
+            import cohere
+        except ImportError:
+            raise ImportError("cohere is required for CohereCrossEncoder. Install it with: pip install cohere")
+
+        base_url_msg = f" at {self.base_url}" if self.base_url else ""
+        logger.info(f"Reranker: initializing Cohere provider with model {self.model}{base_url_msg}")
+
+        # Build client kwargs, only including base_url if set (for Azure or custom endpoints)
+        client_kwargs = {"api_key": self.api_key, "timeout": self.timeout}
+        if self.base_url:
+            client_kwargs["base_url"] = self.base_url
+        self._client = cohere.Client(**client_kwargs)
+        logger.info("Reranker: Cohere provider initialized")
+
+    async def predict(self, pairs: list[tuple[str, str]]) -> list[float]:
+        """
+        Score query-document pairs using the Cohere Rerank API.
+
         Args:
             pairs: List of (query, document) tuples to score
 
@@ -230,50 +456,312 @@ class RemoteTEICrossEncoder(CrossEncoderModel):
         if not pairs:
             return []
 
-        all_scores = []
+        # Run sync Cohere API calls in thread pool
+        loop = asyncio.get_event_loop()
+        return await loop.run_in_executor(None, self._predict_sync, pairs)
 
-        # Process in batches
-        for i in range(0, len(pairs), self.batch_size):
-            batch = pairs[i : i + self.batch_size]
+    def _predict_sync(self, pairs: list[tuple[str, str]]) -> list[float]:
+        """Synchronous predict implementation for Cohere API."""
+        # Group pairs by query for efficient batching
+        # Cohere rerank expects one query with multiple documents
+        query_groups: dict[str, list[tuple[int, str]]] = {}
+        for idx, (query, text) in enumerate(pairs):
+            if query not in query_groups:
+                query_groups[query] = []
+            query_groups[query].append((idx, text))
 
-            # TEI rerank endpoint expects query and texts separately
-            # All pairs in a batch should have the same query for optimal performance
-            # but we handle mixed queries by making separate requests per unique query
-            query_groups: dict[str, list[tuple[int, str]]] = {}
-            for idx, (query, text) in enumerate(batch):
-                if query not in query_groups:
-                    query_groups[query] = []
-                query_groups[query].append((idx, text))
+        all_scores = [0.0] * len(pairs)
 
-            batch_scores = [0.0] * len(batch)
+        for query, indexed_texts in query_groups.items():
+            texts = [text for _, text in indexed_texts]
+            indices = [idx for idx, _ in indexed_texts]
 
-            for query, indexed_texts in query_groups.items():
-                texts = [text for _, text in indexed_texts]
-                indices = [idx for idx, _ in indexed_texts]
+            response = self._client.rerank(
+                query=query,
+                documents=texts,
+                model=self.model,
+                return_documents=False,
+            )
 
-                try:
-                    response = self._request_with_retry(
-                        "POST",
-                        f"{self.base_url}/rerank",
-                        json={
-                            "query": query,
-                            "texts": texts,
-                            "return_text": False,
-                        },
-                    )
-                    results = response.json()
+            # Map scores back to original positions
+            for result in response.results:
+                original_idx = result.index
+                score = result.relevance_score
+                all_scores[indices[original_idx]] = score
 
-                    # TEI returns results sorted by score descending, with original index
-                    for result in results:
-                        original_idx = result["index"]
-                        score = result["score"]
-                        # Map back to batch position
-                        batch_scores[indices[original_idx]] = score
+        return all_scores
 
-                except httpx.HTTPError as e:
-                    raise RuntimeError(f"TEI rerank request failed: {e}")
 
-            all_scores.extend(batch_scores)
+class RRFPassthroughCrossEncoder(CrossEncoderModel):
+    """
+    Passthrough cross-encoder that preserves RRF scores without neural reranking.
+
+    This is useful for:
+    - Testing retrieval quality without reranking overhead
+    - Deployments where reranking latency is unacceptable
+    - Debugging to isolate retrieval vs reranking issues
+    """
+
+    def __init__(self):
+        """Initialize RRF passthrough cross-encoder."""
+        pass
+
+    @property
+    def provider_name(self) -> str:
+        return "rrf"
+
+    async def initialize(self) -> None:
+        """No initialization needed."""
+        logger.info("Reranker: RRF passthrough provider initialized (neural reranking disabled)")
+
+    async def predict(self, pairs: list[tuple[str, str]]) -> list[float]:
+        """
+        Return neutral scores - actual ranking uses RRF scores from retrieval.
+
+        Args:
+            pairs: List of (query, document) tuples (ignored)
+
+        Returns:
+            List of 0.5 scores (neutral, lets RRF scores dominate)
+        """
+        # Return neutral scores so RRF ranking is preserved
+        return [0.5] * len(pairs)
+
+
+class FlashRankCrossEncoder(CrossEncoderModel):
+    """
+    FlashRank cross-encoder implementation.
+
+    FlashRank is an ultra-lite reranking library that runs on CPU without
+    requiring PyTorch or Transformers. It's ideal for serverless deployments
+    with minimal cold-start overhead.
+
+    Available models:
+    - ms-marco-TinyBERT-L-2-v2: Fastest, ~4MB
+    - ms-marco-MiniLM-L-12-v2: Best quality, ~34MB (default)
+    - rank-T5-flan: Best zero-shot, ~110MB
+    - ms-marco-MultiBERT-L-12: Multi-lingual, ~150MB
+    """
+
+    # Shared executor for CPU-bound reranking
+    _executor: ThreadPoolExecutor | None = None
+    _max_concurrent: int = 4
+
+    def __init__(
+        self,
+        model_name: str | None = None,
+        cache_dir: str | None = None,
+        max_length: int = 512,
+        max_concurrent: int = 4,
+    ):
+        """
+        Initialize FlashRank cross-encoder.
+
+        Args:
+            model_name: FlashRank model name. Default: ms-marco-MiniLM-L-12-v2
+            cache_dir: Directory to cache downloaded models. Default: system cache
+            max_length: Maximum sequence length for reranking. Default: 512
+            max_concurrent: Maximum concurrent reranking calls. Default: 4
+        """
+        self.model_name = model_name or DEFAULT_RERANKER_FLASHRANK_MODEL
+        self.cache_dir = cache_dir or DEFAULT_RERANKER_FLASHRANK_CACHE_DIR
+        self.max_length = max_length
+        self._ranker = None
+        FlashRankCrossEncoder._max_concurrent = max_concurrent
+
+    @property
+    def provider_name(self) -> str:
+        return "flashrank"
+
+    async def initialize(self) -> None:
+        """Load the FlashRank model."""
+        if self._ranker is not None:
+            return
+
+        try:
+            from flashrank import Ranker  # type: ignore[import-untyped]
+        except ImportError:
+            raise ImportError("flashrank is required for FlashRankCrossEncoder. Install it with: pip install flashrank")
+
+        logger.info(f"Reranker: initializing FlashRank provider with model {self.model_name}")
+
+        # Initialize ranker with optional cache directory
+        ranker_kwargs = {"model_name": self.model_name, "max_length": self.max_length}
+        if self.cache_dir:
+            ranker_kwargs["cache_dir"] = self.cache_dir
+
+        self._ranker = Ranker(**ranker_kwargs)
+
+        # Initialize shared executor
+        if FlashRankCrossEncoder._executor is None:
+            FlashRankCrossEncoder._executor = ThreadPoolExecutor(
+                max_workers=FlashRankCrossEncoder._max_concurrent,
+                thread_name_prefix="flashrank",
+            )
+            logger.info(
+                f"Reranker: FlashRank provider initialized (max_concurrent={FlashRankCrossEncoder._max_concurrent})"
+            )
+        else:
+            logger.info("Reranker: FlashRank provider initialized (using existing executor)")
+
+    def _predict_sync(self, pairs: list[tuple[str, str]]) -> list[float]:
+        """Synchronous predict - processes each query group."""
+        from flashrank import RerankRequest  # type: ignore[import-untyped]
+
+        if not pairs:
+            return []
+
+        # Group pairs by query
+        query_groups: dict[str, list[tuple[int, str]]] = {}
+        for idx, (query, text) in enumerate(pairs):
+            if query not in query_groups:
+                query_groups[query] = []
+            query_groups[query].append((idx, text))
+
+        all_scores = [0.0] * len(pairs)
+
+        for query, indexed_texts in query_groups.items():
+            # Build passages list for FlashRank
+            passages = [{"id": i, "text": text} for i, (_, text) in enumerate(indexed_texts)]
+            global_indices = [idx for idx, _ in indexed_texts]
+
+            # Create rerank request
+            request = RerankRequest(query=query, passages=passages)
+            results = self._ranker.rerank(request)
+
+            # Map scores back to original positions
+            for result in results:
+                local_idx = result["id"]
+                score = result["score"]
+                global_idx = global_indices[local_idx]
+                all_scores[global_idx] = score
+
+        return all_scores
+
+    async def predict(self, pairs: list[tuple[str, str]]) -> list[float]:
+        """
+        Score query-document pairs using FlashRank.
+
+        Args:
+            pairs: List of (query, document) tuples to score
+
+        Returns:
+            List of relevance scores (higher = more relevant)
+        """
+        if self._ranker is None:
+            raise RuntimeError("Reranker not initialized. Call initialize() first.")
+
+        # Run in thread pool to avoid blocking event loop
+        loop = asyncio.get_event_loop()
+        return await loop.run_in_executor(FlashRankCrossEncoder._executor, self._predict_sync, pairs)
+
+
+class LiteLLMCrossEncoder(CrossEncoderModel):
+    """
+    LiteLLM cross-encoder implementation using LiteLLM proxy's /rerank endpoint.
+
+    LiteLLM provides a unified interface for multiple reranking providers via
+    the Cohere-compatible /rerank endpoint.
+    See: https://docs.litellm.ai/docs/rerank
+
+    Supported providers via LiteLLM:
+    - Cohere (rerank-english-v3.0, etc.) - prefix with cohere/
+    - Together AI - prefix with together_ai/
+    - Azure AI - prefix with azure_ai/
+    - Jina AI - prefix with jina_ai/
+    - AWS Bedrock - prefix with bedrock/
+    - Voyage AI - prefix with voyage/
+    """
+
+    def __init__(
+        self,
+        api_base: str = DEFAULT_LITELLM_API_BASE,
+        api_key: str | None = None,
+        model: str = DEFAULT_RERANKER_LITELLM_MODEL,
+        timeout: float = 60.0,
+    ):
+        """
+        Initialize LiteLLM cross-encoder client.
+
+        Args:
+            api_base: Base URL of the LiteLLM proxy (default: http://localhost:4000)
+            api_key: API key for the LiteLLM proxy (optional, depends on proxy config)
+            model: Reranking model name (default: cohere/rerank-english-v3.0)
+                   Use provider prefix (e.g., cohere/, together_ai/, voyage/)
+            timeout: Request timeout in seconds (default: 60.0)
+        """
+        self.api_base = api_base.rstrip("/")
+        self.api_key = api_key
+        self.model = model
+        self.timeout = timeout
+        self._async_client: httpx.AsyncClient | None = None
+
+    @property
+    def provider_name(self) -> str:
+        return "litellm"
+
+    async def initialize(self) -> None:
+        """Initialize the async HTTP client."""
+        if self._async_client is not None:
+            return
+
+        logger.info(f"Reranker: initializing LiteLLM provider at {self.api_base} with model {self.model}")
+
+        headers = {"Content-Type": "application/json"}
+        if self.api_key:
+            headers["Authorization"] = f"Bearer {self.api_key}"
+
+        self._async_client = httpx.AsyncClient(timeout=self.timeout, headers=headers)
+        logger.info("Reranker: LiteLLM provider initialized")
+
+    async def predict(self, pairs: list[tuple[str, str]]) -> list[float]:
+        """
+        Score query-document pairs using the LiteLLM proxy's /rerank endpoint.
+
+        Args:
+            pairs: List of (query, document) tuples to score
+
+        Returns:
+            List of relevance scores
+        """
+        if self._async_client is None:
+            raise RuntimeError("Reranker not initialized. Call initialize() first.")
+
+        if not pairs:
+            return []
+
+        # Group pairs by query (LiteLLM rerank expects one query with multiple documents)
+        query_groups: dict[str, list[tuple[int, str]]] = {}
+        for idx, (query, text) in enumerate(pairs):
+            if query not in query_groups:
+                query_groups[query] = []
+            query_groups[query].append((idx, text))
+
+        all_scores = [0.0] * len(pairs)
+
+        for query, indexed_texts in query_groups.items():
+            texts = [text for _, text in indexed_texts]
+            indices = [idx for idx, _ in indexed_texts]
+
+            # LiteLLM /rerank follows Cohere API format
+            response = await self._async_client.post(
+                f"{self.api_base}/rerank",
+                json={
+                    "model": self.model,
+                    "query": query,
+                    "documents": texts,
+                    "top_n": len(texts),  # Return all scores
+                },
+            )
+            response.raise_for_status()
+            result = response.json()
+
+            # Map scores back to original positions
+            # Response format: {"results": [{"index": 0, "relevance_score": 0.9}, ...]}
+            for item in result.get("results", []):
+                original_idx = item["index"]
+                score = item.get("relevance_score", item.get("score", 0.0))
+                all_scores[indices[original_idx]] = score
 
         return all_scores
 
@@ -293,10 +781,35 @@ def create_cross_encoder_from_env() -> CrossEncoderModel:
         url = os.environ.get(ENV_RERANKER_TEI_URL)
         if not url:
             raise ValueError(f"{ENV_RERANKER_TEI_URL} is required when {ENV_RERANKER_PROVIDER} is 'tei'")
-        return RemoteTEICrossEncoder(base_url=url)
+        batch_size = int(os.environ.get(ENV_RERANKER_TEI_BATCH_SIZE, str(DEFAULT_RERANKER_TEI_BATCH_SIZE)))
+        max_concurrent = int(os.environ.get(ENV_RERANKER_TEI_MAX_CONCURRENT, str(DEFAULT_RERANKER_TEI_MAX_CONCURRENT)))
+        return RemoteTEICrossEncoder(base_url=url, batch_size=batch_size, max_concurrent=max_concurrent)
     elif provider == "local":
         model = os.environ.get(ENV_RERANKER_LOCAL_MODEL)
         model_name = model or DEFAULT_RERANKER_LOCAL_MODEL
-        return LocalSTCrossEncoder(model_name=model_name)
+        max_concurrent = int(
+            os.environ.get(ENV_RERANKER_LOCAL_MAX_CONCURRENT, str(DEFAULT_RERANKER_LOCAL_MAX_CONCURRENT))
+        )
+        return LocalSTCrossEncoder(model_name=model_name, max_concurrent=max_concurrent)
+    elif provider == "cohere":
+        api_key = os.environ.get(ENV_COHERE_API_KEY)
+        if not api_key:
+            raise ValueError(f"{ENV_COHERE_API_KEY} is required when {ENV_RERANKER_PROVIDER} is 'cohere'")
+        model = os.environ.get(ENV_RERANKER_COHERE_MODEL, DEFAULT_RERANKER_COHERE_MODEL)
+        base_url = os.environ.get(ENV_RERANKER_COHERE_BASE_URL) or None
+        return CohereCrossEncoder(api_key=api_key, model=model, base_url=base_url)
+    elif provider == "flashrank":
+        model = os.environ.get(ENV_RERANKER_FLASHRANK_MODEL, DEFAULT_RERANKER_FLASHRANK_MODEL)
+        cache_dir = os.environ.get(ENV_RERANKER_FLASHRANK_CACHE_DIR, DEFAULT_RERANKER_FLASHRANK_CACHE_DIR)
+        return FlashRankCrossEncoder(model_name=model, cache_dir=cache_dir)
+    elif provider == "litellm":
+        api_base = os.environ.get(ENV_LITELLM_API_BASE, DEFAULT_LITELLM_API_BASE)
+        api_key = os.environ.get(ENV_LITELLM_API_KEY)
+        model = os.environ.get(ENV_RERANKER_LITELLM_MODEL, DEFAULT_RERANKER_LITELLM_MODEL)
+        return LiteLLMCrossEncoder(api_base=api_base, api_key=api_key, model=model)
+    elif provider == "rrf":
+        return RRFPassthroughCrossEncoder()
     else:
-        raise ValueError(f"Unknown reranker provider: {provider}. Supported: 'local', 'tei'")
+        raise ValueError(
+            f"Unknown reranker provider: {provider}. Supported: 'local', 'tei', 'cohere', 'flashrank', 'litellm', 'rrf'"
+        )

hindsight-api/hindsight_api/engine/db_budget.py

@@ -0,0 +1,284 @@
+"""
+Database connection budget management.
+
+Limits concurrent database connections per operation to prevent
+a single operation (e.g., recall with parallel queries) from
+exhausting the connection pool.
+"""
+
+import asyncio
+import logging
+import uuid
+from contextlib import asynccontextmanager
+from dataclasses import dataclass, field
+from typing import TYPE_CHECKING, AsyncIterator
+
+if TYPE_CHECKING:
+    import asyncpg
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class OperationBudget:
+    """
+    Tracks connection budget for a single operation.
+
+    Each operation gets a semaphore limiting its concurrent connections.
+    """
+
+    operation_id: str
+    max_connections: int
+    semaphore: asyncio.Semaphore = field(init=False)
+    active_count: int = field(default=0, init=False)
+
+    def __post_init__(self):
+        self.semaphore = asyncio.Semaphore(self.max_connections)
+
+
+class ConnectionBudgetManager:
+    """
+    Manages per-operation connection budgets.
+
+    Usage:
+        manager = ConnectionBudgetManager(default_budget=4)
+
+        # Start an operation
+        async with manager.operation(max_connections=2) as op:
+            # Acquire connections within the budget
+            async with op.acquire(pool) as conn:
+                await conn.fetch(...)
+
+            # Multiple connections respect the budget
+            async with op.acquire(pool) as conn1, op.acquire(pool) as conn2:
+                # At most 2 concurrent connections for this operation
+                ...
+    """
+
+    def __init__(self, default_budget: int = 4):
+        """
+        Initialize the budget manager.
+
+        Args:
+            default_budget: Default max connections per operation
+        """
+        self.default_budget = default_budget
+        self._operations: dict[str, OperationBudget] = {}
+        self._lock = asyncio.Lock()
+
+    @asynccontextmanager
+    async def operation(
+        self,
+        max_connections: int | None = None,
+        operation_id: str | None = None,
+    ) -> AsyncIterator["BudgetedOperation"]:
+        """
+        Create a budgeted operation context.
+
+        Args:
+            max_connections: Max concurrent connections for this operation.
+                           Defaults to manager's default_budget.
+            operation_id: Optional custom operation ID. Auto-generated if not provided.
+
+        Yields:
+            BudgetedOperation context for acquiring connections
+        """
+        op_id = operation_id or f"op-{uuid.uuid4().hex[:12]}"
+        budget = max_connections or self.default_budget
+
+        async with self._lock:
+            if op_id in self._operations:
+                raise ValueError(f"Operation {op_id} already exists")
+            self._operations[op_id] = OperationBudget(op_id, budget)
+
+        try:
+            yield BudgetedOperation(self, op_id)
+        finally:
+            async with self._lock:
+                self._operations.pop(op_id, None)
+
+    def _get_budget(self, operation_id: str) -> OperationBudget:
+        """Get budget for an operation (internal use)."""
+        budget = self._operations.get(operation_id)
+        if not budget:
+            raise ValueError(f"Operation {operation_id} not found")
+        return budget
+
+
+class BudgetedOperation:
+    """
+    A single operation with connection budget.
+
+    Provides methods to acquire connections within the budget.
+    """
+
+    def __init__(self, manager: ConnectionBudgetManager, operation_id: str):
+        self._manager = manager
+        self.operation_id = operation_id
+
+    @property
+    def budget(self) -> OperationBudget:
+        """Get the budget for this operation."""
+        return self._manager._get_budget(self.operation_id)
+
+    @asynccontextmanager
+    async def acquire(self, pool: "asyncpg.Pool") -> AsyncIterator["asyncpg.Connection"]:
+        """
+        Acquire a connection within the operation's budget.
+
+        Blocks if the operation has reached its connection limit.
+
+        Args:
+            pool: asyncpg connection pool
+
+        Yields:
+            Database connection
+        """
+        budget = self.budget
+        async with budget.semaphore:
+            budget.active_count += 1
+            conn = await pool.acquire()
+            try:
+                yield conn
+            finally:
+                budget.active_count -= 1
+                await pool.release(conn)
+
+    def wrap_pool(self, pool: "asyncpg.Pool") -> "BudgetedPool":
+        """
+        Wrap a pool with this operation's budget.
+
+        The returned BudgetedPool can be passed to functions expecting a pool,
+        and all acquire() calls will be limited by this operation's budget.
+
+        Args:
+            pool: asyncpg connection pool to wrap
+
+        Returns:
+            BudgetedPool that limits connections to this operation's budget
+        """
+        return BudgetedPool(pool, self)
+
+    async def acquire_many(
+        self,
+        pool: "asyncpg.Pool",
+        count: int,
+    ) -> AsyncIterator[list["asyncpg.Connection"]]:
+        """
+        Acquire multiple connections within the budget.
+
+        Note: This acquires connections sequentially to respect the budget.
+        For parallel acquisition, use multiple acquire() calls with asyncio.gather().
+
+        Args:
+            pool: asyncpg connection pool
+            count: Number of connections to acquire
+
+        Yields:
+            List of database connections
+        """
+        connections = []
+        try:
+            for _ in range(count):
+                conn = await pool.acquire()
+                connections.append(conn)
+            yield connections
+        finally:
+            for conn in connections:
+                await pool.release(conn)
+
+
+# Global default manager instance
+_default_manager: ConnectionBudgetManager | None = None
+
+
+def get_budget_manager(default_budget: int = 4) -> ConnectionBudgetManager:
+    """
+    Get or create the global budget manager.
+
+    Args:
+        default_budget: Default max connections per operation
+
+    Returns:
+        Global ConnectionBudgetManager instance
+    """
+    global _default_manager
+    if _default_manager is None:
+        _default_manager = ConnectionBudgetManager(default_budget=default_budget)
+    return _default_manager
+
+
+@asynccontextmanager
+async def budgeted_operation(
+    max_connections: int | None = None,
+    operation_id: str | None = None,
+    default_budget: int = 4,
+) -> AsyncIterator[BudgetedOperation]:
+    """
+    Convenience function to create a budgeted operation.
+
+    Args:
+        max_connections: Max concurrent connections for this operation
+        operation_id: Optional custom operation ID
+        default_budget: Default budget if manager not yet created
+
+    Yields:
+        BudgetedOperation context
+
+    Example:
+        async with budgeted_operation(max_connections=2) as op:
+            async with op.acquire(pool) as conn:
+                await conn.fetch(...)
+    """
+    manager = get_budget_manager(default_budget)
+    async with manager.operation(max_connections, operation_id) as op:
+        yield op
+
+
+class BudgetedPool:
+    """
+    A pool wrapper that limits concurrent connection acquisitions.
+
+    This can be passed to functions expecting a pool, and acquire()
+    calls will be limited by the budget semaphore.
+
+    Usage:
+        async with budgeted_operation(max_connections=4) as op:
+            budgeted_pool = op.wrap_pool(pool)
+            # Pass budgeted_pool to functions that expect a pool
+            await some_function(budgeted_pool, ...)
+    """
+
+    def __init__(self, pool: "asyncpg.Pool", operation: BudgetedOperation):
+        self._pool = pool
+        self._operation = operation
+
+    async def acquire(self) -> "asyncpg.Connection":
+        """
+        Acquire a connection within the budget.
+
+        Note: Caller must release the connection when done.
+        Prefer using as context manager via acquire_with_retry or op.acquire().
+        """
+        budget = self._operation.budget
+        await budget.semaphore.acquire()
+        budget.active_count += 1
+        try:
+            return await self._pool.acquire()
+        except Exception:
+            budget.active_count -= 1
+            budget.semaphore.release()
+            raise
+
+    async def release(self, conn: "asyncpg.Connection") -> None:
+        """Release a connection back to the pool."""
+        budget = self._operation.budget
+        try:
+            await self._pool.release(conn)
+        finally:
+            budget.active_count -= 1
+            budget.semaphore.release()
+
+    def __getattr__(self, name):
+        """Proxy other attributes to the underlying pool."""
+        return getattr(self._pool, name)

hindsight-api/hindsight_api/engine/db_utils.py

@@ -83,11 +83,22 @@ async def acquire_with_retry(pool: asyncpg.Pool, max_retries: int = DEFAULT_MAX_
     Yields:
         An asyncpg connection
     """
+    import time
+
+    start = time.time()
 
     async def acquire():
         return await pool.acquire()
 
     conn = await retry_with_backoff(acquire, max_retries=max_retries)
+    acquire_time = time.time() - start
+
+    # Log slow connection acquisitions (indicates pool contention)
+    if acquire_time > 0.05:  # 50ms threshold
+        pool_size = pool.get_size()
+        pool_free = pool.get_idle_size()
+        logger.warning(f"[DB POOL] Slow acquire: {acquire_time:.3f}s | size={pool_size}, idle={pool_free}")
+
     try:
         yield conn
     finally:

hindsight-api/hindsight_api/engine/embeddings.py

@@ -3,8 +3,8 @@ Embeddings abstraction for the memory system.
 
 Provides an interface for generating embeddings with different backends.
 
-IMPORTANT: All embeddings must produce 384-dimensional vectors to match
-the database schema (pgvector column defined as vector(384)).
+The embedding dimension is auto-detected from the model at initialization.
+The database schema is automatically adjusted to match the model's dimension.
 
 Configuration via environment variables - see hindsight_api.config for all env var names.
 """
@@ -16,12 +16,25 @@ from abc import ABC, abstractmethod
 import httpx
 
 from ..config import (
+    DEFAULT_EMBEDDINGS_COHERE_MODEL,
+    DEFAULT_EMBEDDINGS_LITELLM_MODEL,
     DEFAULT_EMBEDDINGS_LOCAL_MODEL,
+    DEFAULT_EMBEDDINGS_OPENAI_MODEL,
     DEFAULT_EMBEDDINGS_PROVIDER,
-    EMBEDDING_DIMENSION,
+    DEFAULT_LITELLM_API_BASE,
+    ENV_COHERE_API_KEY,
+    ENV_EMBEDDINGS_COHERE_BASE_URL,
+    ENV_EMBEDDINGS_COHERE_MODEL,
+    ENV_EMBEDDINGS_LITELLM_MODEL,
     ENV_EMBEDDINGS_LOCAL_MODEL,
+    ENV_EMBEDDINGS_OPENAI_API_KEY,
+    ENV_EMBEDDINGS_OPENAI_BASE_URL,
+    ENV_EMBEDDINGS_OPENAI_MODEL,
     ENV_EMBEDDINGS_PROVIDER,
     ENV_EMBEDDINGS_TEI_URL,
+    ENV_LITELLM_API_BASE,
+    ENV_LITELLM_API_KEY,
+    ENV_LLM_API_KEY,
 )
 
 logger = logging.getLogger(__name__)
@@ -31,8 +44,8 @@ class Embeddings(ABC):
     """
     Abstract base class for embedding generation.
 
-    All implementations MUST generate 384-dimensional embeddings to match
-    the database schema.
+    The embedding dimension is determined by the model and detected at initialization.
+    The database schema is automatically adjusted to match the model's dimension.
     """
 
     @property
@@ -41,6 +54,12 @@ class Embeddings(ABC):
         """Return a human-readable name for this provider (e.g., 'local', 'tei')."""
         pass
 
+    @property
+    @abstractmethod
+    def dimension(self) -> int:
+        """Return the embedding dimension produced by this model."""
+        pass
+
     @abstractmethod
     async def initialize(self) -> None:
         """
@@ -54,13 +73,13 @@ class Embeddings(ABC):
     @abstractmethod
     def encode(self, texts: list[str]) -> list[list[float]]:
         """
-        Generate 384-dimensional embeddings for a list of texts.
+        Generate embeddings for a list of texts.
 
         Args:
             texts: List of text strings to encode
 
         Returns:
-            List of 384-dimensional embedding vectors (each is a list of floats)
+            List of embedding vectors (each is a list of floats)
         """
         pass
 
@@ -70,9 +89,7 @@ class LocalSTEmbeddings(Embeddings):
     Local embeddings implementation using SentenceTransformers.
 
     Call initialize() during startup to load the model and avoid cold starts.
-
-    Default model is BAAI/bge-small-en-v1.5 which produces 384-dimensional
-    embeddings matching the database schema.
+    The embedding dimension is auto-detected from the model.
     """
 
     def __init__(self, model_name: str | None = None):
@@ -81,16 +98,22 @@ class LocalSTEmbeddings(Embeddings):
 
         Args:
             model_name: Name of the SentenceTransformer model to use.
-                       Must produce 384-dimensional embeddings.
                        Default: BAAI/bge-small-en-v1.5
         """
         self.model_name = model_name or DEFAULT_EMBEDDINGS_LOCAL_MODEL
         self._model = None
+        self._dimension: int | None = None
 
     @property
     def provider_name(self) -> str:
         return "local"
 
+    @property
+    def dimension(self) -> int:
+        if self._dimension is None:
+            raise RuntimeError("Embeddings not initialized. Call initialize() first.")
+        return self._dimension
+
     async def initialize(self) -> None:
         """Load the embedding model."""
         if self._model is not None:
@@ -112,26 +135,18 @@ class LocalSTEmbeddings(Embeddings):
             model_kwargs={"low_cpu_mem_usage": False, "device_map": None},
         )
 
-        # Validate dimension matches database schema
-        model_dim = self._model.get_sentence_embedding_dimension()
-        if model_dim != EMBEDDING_DIMENSION:
-            raise ValueError(
-                f"Model {self.model_name} produces {model_dim}-dimensional embeddings, "
-                f"but database schema requires {EMBEDDING_DIMENSION} dimensions. "
-                f"Use a model that produces {EMBEDDING_DIMENSION}-dimensional embeddings."
-            )
-
-        logger.info(f"Embeddings: local provider initialized (dim: {model_dim})")
+        self._dimension = self._model.get_sentence_embedding_dimension()
+        logger.info(f"Embeddings: local provider initialized (dim: {self._dimension})")
 
     def encode(self, texts: list[str]) -> list[list[float]]:
         """
-        Generate 384-dimensional embeddings for a list of texts.
+        Generate embeddings for a list of texts.
 
         Args:
             texts: List of text strings to encode
 
         Returns:
-            List of 384-dimensional embedding vectors
+            List of embedding vectors
         """
         if self._model is None:
             raise RuntimeError("Embeddings not initialized. Call initialize() first.")
@@ -146,7 +161,7 @@ class RemoteTEIEmbeddings(Embeddings):
     TEI provides a high-performance inference server for embedding models.
     See: https://github.com/huggingface/text-embeddings-inference
 
-    The server should be running a model that produces 384-dimensional embeddings.
+    The embedding dimension is auto-detected from the server at initialization.
     """
 
     def __init__(
@@ -174,11 +189,18 @@ class RemoteTEIEmbeddings(Embeddings):
         self.retry_delay = retry_delay
         self._client: httpx.Client | None = None
         self._model_id: str | None = None
+        self._dimension: int | None = None
 
     @property
     def provider_name(self) -> str:
         return "tei"
 
+    @property
+    def dimension(self) -> int:
+        if self._dimension is None:
+            raise RuntimeError("Embeddings not initialized. Call initialize() first.")
+        return self._dimension
+
     def _request_with_retry(self, method: str, url: str, **kwargs) -> httpx.Response:
         """Make an HTTP request with automatic retries on transient errors."""
         import time
@@ -229,7 +251,24 @@ class RemoteTEIEmbeddings(Embeddings):
             response = self._request_with_retry("GET", f"{self.base_url}/info")
             info = response.json()
             self._model_id = info.get("model_id", "unknown")
-            logger.info(f"Embeddings: TEI provider initialized (model: {self._model_id})")
+
+            # Get dimension from server info or by doing a test embedding
+            if "max_input_length" in info and "model_dtype" in info:
+                # Try to get dimension from info endpoint (some TEI versions expose it)
+                # If not available, do a test embedding
+                pass
+
+            # Do a test embedding to detect dimension
+            test_response = self._request_with_retry(
+                "POST",
+                f"{self.base_url}/embed",
+                json={"inputs": ["test"]},
+            )
+            test_embeddings = test_response.json()
+            if test_embeddings and len(test_embeddings) > 0:
+                self._dimension = len(test_embeddings[0])
+
+            logger.info(f"Embeddings: TEI provider initialized (model: {self._model_id}, dim: {self._dimension})")
         except httpx.HTTPError as e:
             raise RuntimeError(f"Failed to connect to TEI server at {self.base_url}: {e}")
 
@@ -269,6 +308,369 @@ class RemoteTEIEmbeddings(Embeddings):
         return all_embeddings
 
 
+class OpenAIEmbeddings(Embeddings):
+    """
+    OpenAI embeddings implementation using the OpenAI API.
+
+    Supports text-embedding-3-small (1536 dims), text-embedding-3-large (3072 dims),
+    and text-embedding-ada-002 (1536 dims, legacy).
+
+    The embedding dimension is auto-detected from the model at initialization.
+    """
+
+    # Known dimensions for OpenAI embedding models
+    MODEL_DIMENSIONS = {
+        "text-embedding-3-small": 1536,
+        "text-embedding-3-large": 3072,
+        "text-embedding-ada-002": 1536,
+    }
+
+    def __init__(
+        self,
+        api_key: str,
+        model: str = DEFAULT_EMBEDDINGS_OPENAI_MODEL,
+        base_url: str | None = None,
+        batch_size: int = 100,
+        max_retries: int = 3,
+    ):
+        """
+        Initialize OpenAI embeddings client.
+
+        Args:
+            api_key: OpenAI API key
+            model: OpenAI embedding model name (default: text-embedding-3-small)
+            base_url: Custom base URL for OpenAI-compatible API (e.g., Azure OpenAI endpoint)
+            batch_size: Maximum batch size for embedding requests (default: 100)
+            max_retries: Maximum number of retries for failed requests (default: 3)
+        """
+        self.api_key = api_key
+        self.model = model
+        self.base_url = base_url
+        self.batch_size = batch_size
+        self.max_retries = max_retries
+        self._client = None
+        self._dimension: int | None = None
+
+    @property
+    def provider_name(self) -> str:
+        return "openai"
+
+    @property
+    def dimension(self) -> int:
+        if self._dimension is None:
+            raise RuntimeError("Embeddings not initialized. Call initialize() first.")
+        return self._dimension
+
+    async def initialize(self) -> None:
+        """Initialize the OpenAI client and detect dimension."""
+        if self._client is not None:
+            return
+
+        try:
+            from openai import OpenAI
+        except ImportError:
+            raise ImportError("openai is required for OpenAIEmbeddings. Install it with: pip install openai")
+
+        base_url_msg = f" at {self.base_url}" if self.base_url else ""
+        logger.info(f"Embeddings: initializing OpenAI provider with model {self.model}{base_url_msg}")
+
+        # Build client kwargs, only including base_url if set (for Azure or custom endpoints)
+        client_kwargs = {"api_key": self.api_key, "max_retries": self.max_retries}
+        if self.base_url:
+            client_kwargs["base_url"] = self.base_url
+        self._client = OpenAI(**client_kwargs)
+
+        # Try to get dimension from known models, otherwise do a test embedding
+        if self.model in self.MODEL_DIMENSIONS:
+            self._dimension = self.MODEL_DIMENSIONS[self.model]
+        else:
+            # Do a test embedding to detect dimension
+            response = self._client.embeddings.create(
+                model=self.model,
+                input=["test"],
+            )
+            if response.data:
+                self._dimension = len(response.data[0].embedding)
+
+        logger.info(f"Embeddings: OpenAI provider initialized (model: {self.model}, dim: {self._dimension})")
+
+    def encode(self, texts: list[str]) -> list[list[float]]:
+        """
+        Generate embeddings using the OpenAI API.
+
+        Args:
+            texts: List of text strings to encode
+
+        Returns:
+            List of embedding vectors
+        """
+        if self._client is None:
+            raise RuntimeError("Embeddings not initialized. Call initialize() first.")
+
+        if not texts:
+            return []
+
+        all_embeddings = []
+
+        # Process in batches
+        for i in range(0, len(texts), self.batch_size):
+            batch = texts[i : i + self.batch_size]
+
+            response = self._client.embeddings.create(
+                model=self.model,
+                input=batch,
+            )
+
+            # Sort by index to ensure correct order
+            batch_embeddings = sorted(response.data, key=lambda x: x.index)
+            all_embeddings.extend([e.embedding for e in batch_embeddings])
+
+        return all_embeddings
+
+
+class CohereEmbeddings(Embeddings):
+    """
+    Cohere embeddings implementation using the Cohere API.
+
+    Supports embed-english-v3.0 (1024 dims) and embed-multilingual-v3.0 (1024 dims).
+
+    The embedding dimension is auto-detected from the model at initialization.
+    """
+
+    # Known dimensions for Cohere embedding models
+    MODEL_DIMENSIONS = {
+        "embed-english-v3.0": 1024,
+        "embed-multilingual-v3.0": 1024,
+        "embed-english-light-v3.0": 384,
+        "embed-multilingual-light-v3.0": 384,
+        "embed-english-v2.0": 4096,
+        "embed-multilingual-v2.0": 768,
+    }
+
+    def __init__(
+        self,
+        api_key: str,
+        model: str = DEFAULT_EMBEDDINGS_COHERE_MODEL,
+        base_url: str | None = None,
+        batch_size: int = 96,
+        timeout: float = 60.0,
+        input_type: str = "search_document",
+    ):
+        """
+        Initialize Cohere embeddings client.
+
+        Args:
+            api_key: Cohere API key
+            model: Cohere embedding model name (default: embed-english-v3.0)
+            base_url: Custom base URL for Cohere-compatible API (e.g., Azure-hosted endpoint)
+            batch_size: Maximum batch size for embedding requests (default: 96, Cohere's limit)
+            timeout: Request timeout in seconds (default: 60.0)
+            input_type: Input type for embeddings (default: search_document).
+                       Options: search_document, search_query, classification, clustering
+        """
+        self.api_key = api_key
+        self.model = model
+        self.base_url = base_url
+        self.batch_size = batch_size
+        self.timeout = timeout
+        self.input_type = input_type
+        self._client = None
+        self._dimension: int | None = None
+
+    @property
+    def provider_name(self) -> str:
+        return "cohere"
+
+    @property
+    def dimension(self) -> int:
+        if self._dimension is None:
+            raise RuntimeError("Embeddings not initialized. Call initialize() first.")
+        return self._dimension
+
+    async def initialize(self) -> None:
+        """Initialize the Cohere client and detect dimension."""
+        if self._client is not None:
+            return
+
+        try:
+            import cohere
+        except ImportError:
+            raise ImportError("cohere is required for CohereEmbeddings. Install it with: pip install cohere")
+
+        base_url_msg = f" at {self.base_url}" if self.base_url else ""
+        logger.info(f"Embeddings: initializing Cohere provider with model {self.model}{base_url_msg}")
+
+        # Build client kwargs, only including base_url if set (for Azure or custom endpoints)
+        client_kwargs = {"api_key": self.api_key, "timeout": self.timeout}
+        if self.base_url:
+            client_kwargs["base_url"] = self.base_url
+        self._client = cohere.Client(**client_kwargs)
+
+        # Try to get dimension from known models, otherwise do a test embedding
+        if self.model in self.MODEL_DIMENSIONS:
+            self._dimension = self.MODEL_DIMENSIONS[self.model]
+        else:
+            # Do a test embedding to detect dimension
+            response = self._client.embed(
+                texts=["test"],
+                model=self.model,
+                input_type=self.input_type,
+            )
+            if response.embeddings:
+                self._dimension = len(response.embeddings[0])
+
+        logger.info(f"Embeddings: Cohere provider initialized (model: {self.model}, dim: {self._dimension})")
+
+    def encode(self, texts: list[str]) -> list[list[float]]:
+        """
+        Generate embeddings using the Cohere API.
+
+        Args:
+            texts: List of text strings to encode
+
+        Returns:
+            List of embedding vectors
+        """
+        if self._client is None:
+            raise RuntimeError("Embeddings not initialized. Call initialize() first.")
+
+        if not texts:
+            return []
+
+        all_embeddings = []
+
+        # Process in batches
+        for i in range(0, len(texts), self.batch_size):
+            batch = texts[i : i + self.batch_size]
+
+            response = self._client.embed(
+                texts=batch,
+                model=self.model,
+                input_type=self.input_type,
+            )
+
+            all_embeddings.extend(response.embeddings)
+
+        return all_embeddings
+
+
+class LiteLLMEmbeddings(Embeddings):
+    """
+    LiteLLM embeddings implementation using LiteLLM proxy's /embeddings endpoint.
+
+    LiteLLM provides a unified interface for multiple embedding providers.
+    The proxy exposes an OpenAI-compatible /embeddings endpoint.
+    See: https://docs.litellm.ai/docs/embedding/supported_embedding
+
+    Supported providers via LiteLLM:
+    - OpenAI (text-embedding-3-small, text-embedding-ada-002, etc.)
+    - Cohere (embed-english-v3.0, etc.) - prefix with cohere/
+    - Vertex AI (textembedding-gecko, etc.) - prefix with vertex_ai/
+    - HuggingFace, Mistral, Voyage AI, etc.
+
+    The embedding dimension is auto-detected from the model at initialization.
+    """
+
+    def __init__(
+        self,
+        api_base: str = DEFAULT_LITELLM_API_BASE,
+        api_key: str | None = None,
+        model: str = DEFAULT_EMBEDDINGS_LITELLM_MODEL,
+        batch_size: int = 100,
+        timeout: float = 60.0,
+    ):
+        """
+        Initialize LiteLLM embeddings client.
+
+        Args:
+            api_base: Base URL of the LiteLLM proxy (default: http://localhost:4000)
+            api_key: API key for the LiteLLM proxy (optional, depends on proxy config)
+            model: Embedding model name (default: text-embedding-3-small)
+                   Use provider prefix for non-OpenAI models (e.g., cohere/embed-english-v3.0)
+            batch_size: Maximum batch size for embedding requests (default: 100)
+            timeout: Request timeout in seconds (default: 60.0)
+        """
+        self.api_base = api_base.rstrip("/")
+        self.api_key = api_key
+        self.model = model
+        self.batch_size = batch_size
+        self.timeout = timeout
+        self._client: httpx.Client | None = None
+        self._dimension: int | None = None
+
+    @property
+    def provider_name(self) -> str:
+        return "litellm"
+
+    @property
+    def dimension(self) -> int:
+        if self._dimension is None:
+            raise RuntimeError("Embeddings not initialized. Call initialize() first.")
+        return self._dimension
+
+    async def initialize(self) -> None:
+        """Initialize the HTTP client and detect embedding dimension."""
+        if self._client is not None:
+            return
+
+        logger.info(f"Embeddings: initializing LiteLLM provider at {self.api_base} with model {self.model}")
+
+        headers = {"Content-Type": "application/json"}
+        if self.api_key:
+            headers["Authorization"] = f"Bearer {self.api_key}"
+
+        self._client = httpx.Client(timeout=self.timeout, headers=headers)
+
+        # Do a test embedding to detect dimension
+        try:
+            response = self._client.post(
+                f"{self.api_base}/embeddings",
+                json={"model": self.model, "input": ["test"]},
+            )
+            response.raise_for_status()
+            result = response.json()
+            if result.get("data") and len(result["data"]) > 0:
+                self._dimension = len(result["data"][0]["embedding"])
+            logger.info(f"Embeddings: LiteLLM provider initialized (model: {self.model}, dim: {self._dimension})")
+        except httpx.HTTPError as e:
+            raise RuntimeError(f"Failed to connect to LiteLLM proxy at {self.api_base}: {e}")
+
+    def encode(self, texts: list[str]) -> list[list[float]]:
+        """
+        Generate embeddings using the LiteLLM proxy.
+
+        Args:
+            texts: List of text strings to encode
+
+        Returns:
+            List of embedding vectors
+        """
+        if self._client is None:
+            raise RuntimeError("Embeddings not initialized. Call initialize() first.")
+
+        if not texts:
+            return []
+
+        all_embeddings = []
+
+        # Process in batches
+        for i in range(0, len(texts), self.batch_size):
+            batch = texts[i : i + self.batch_size]
+
+            response = self._client.post(
+                f"{self.api_base}/embeddings",
+                json={"model": self.model, "input": batch},
+            )
+            response.raise_for_status()
+            result = response.json()
+
+            # Sort by index to ensure correct order
+            batch_embeddings = sorted(result["data"], key=lambda x: x["index"])
+            all_embeddings.extend([e["embedding"] for e in batch_embeddings])
+
+        return all_embeddings
+
+
 def create_embeddings_from_env() -> Embeddings:
     """
     Create an Embeddings instance based on environment variables.
@@ -289,5 +691,30 @@ def create_embeddings_from_env() -> Embeddings:
         model = os.environ.get(ENV_EMBEDDINGS_LOCAL_MODEL)
         model_name = model or DEFAULT_EMBEDDINGS_LOCAL_MODEL
         return LocalSTEmbeddings(model_name=model_name)
+    elif provider == "openai":
+        # Use dedicated embeddings API key, or fall back to LLM API key
+        api_key = os.environ.get(ENV_EMBEDDINGS_OPENAI_API_KEY) or os.environ.get(ENV_LLM_API_KEY)
+        if not api_key:
+            raise ValueError(
+                f"{ENV_EMBEDDINGS_OPENAI_API_KEY} or {ENV_LLM_API_KEY} is required "
+                f"when {ENV_EMBEDDINGS_PROVIDER} is 'openai'"
+            )
+        model = os.environ.get(ENV_EMBEDDINGS_OPENAI_MODEL, DEFAULT_EMBEDDINGS_OPENAI_MODEL)
+        base_url = os.environ.get(ENV_EMBEDDINGS_OPENAI_BASE_URL) or None
+        return OpenAIEmbeddings(api_key=api_key, model=model, base_url=base_url)
+    elif provider == "cohere":
+        api_key = os.environ.get(ENV_COHERE_API_KEY)
+        if not api_key:
+            raise ValueError(f"{ENV_COHERE_API_KEY} is required when {ENV_EMBEDDINGS_PROVIDER} is 'cohere'")
+        model = os.environ.get(ENV_EMBEDDINGS_COHERE_MODEL, DEFAULT_EMBEDDINGS_COHERE_MODEL)
+        base_url = os.environ.get(ENV_EMBEDDINGS_COHERE_BASE_URL) or None
+        return CohereEmbeddings(api_key=api_key, model=model, base_url=base_url)
+    elif provider == "litellm":
+        api_base = os.environ.get(ENV_LITELLM_API_BASE, DEFAULT_LITELLM_API_BASE)
+        api_key = os.environ.get(ENV_LITELLM_API_KEY)
+        model = os.environ.get(ENV_EMBEDDINGS_LITELLM_MODEL, DEFAULT_EMBEDDINGS_LITELLM_MODEL)
+        return LiteLLMEmbeddings(api_base=api_base, api_key=api_key, model=model)
     else:
-        raise ValueError(f"Unknown embeddings provider: {provider}. Supported: 'local', 'tei'")
+        raise ValueError(
+            f"Unknown embeddings provider: {provider}. Supported: 'local', 'tei', 'openai', 'cohere', 'litellm'"
+        )

hindsight-api/hindsight_api/engine/entity_resolver.py

@@ -11,6 +11,7 @@ from difflib import SequenceMatcher
 import asyncpg
 
 from .db_utils import acquire_with_retry
+from .memory_engine import fq_table
 
 # Load spaCy model (singleton)
 _nlp = None
@@ -68,9 +69,9 @@ class EntityResolver:
     ) -> list[str]:
         # Query ALL candidates for this bank
         all_entities = await conn.fetch(
-            """
+            f"""
             SELECT canonical_name, id, metadata, last_seen, mention_count
-            FROM entities
+            FROM {fq_table("entities")}
             WHERE bank_id = $1
             """,
             bank_id,
@@ -82,11 +83,11 @@ class EntityResolver:
         # Query ALL co-occurrences for this bank's entities in one query
         # This builds a map of entity_id -> set of co-occurring entity names
         all_cooccurrences = await conn.fetch(
-            """
+            f"""
             SELECT ec.entity_id_1, ec.entity_id_2, ec.cooccurrence_count
-            FROM entity_cooccurrences ec
-            WHERE ec.entity_id_1 IN (SELECT id FROM entities WHERE bank_id = $1)
-               OR ec.entity_id_2 IN (SELECT id FROM entities WHERE bank_id = $1)
+            FROM {fq_table("entity_cooccurrences")} ec
+            WHERE ec.entity_id_1 IN (SELECT id FROM {fq_table("entities")} WHERE bank_id = $1)
+               OR ec.entity_id_2 IN (SELECT id FROM {fq_table("entities")} WHERE bank_id = $1)
             """,
             bank_id,
         )
@@ -195,8 +196,8 @@ class EntityResolver:
         # Batch update existing entities
         if entities_to_update:
             await conn.executemany(
-                """
-                UPDATE entities SET
+                f"""
+                UPDATE {fq_table("entities")} SET
                     mention_count = mention_count + 1,
                     last_seen = $2
                 WHERE id = $1::uuid
@@ -208,7 +209,7 @@ class EntityResolver:
         # This handles duplicates via ON CONFLICT and returns all IDs
         if entities_to_create:
             # Group entities by canonical name (lowercase) to handle duplicates within batch
-            # For duplicates, we only insert once and reuse the ID
+            # For duplicates, we only insert once and reuse the ID, but track the count
             unique_entities = {}  # lowercase_name -> (entity_data, event_date, [indices])
             for idx, entity_data, event_date in entities_to_create:
                 name_lower = entity_data["text"].lower()
@@ -222,29 +223,32 @@ class EntityResolver:
             # Use a single query with unnest for speed
             entity_names = []
             entity_dates = []
+            entity_counts = []  # Track how many times each entity appears in this batch
             indices_map = []  # Maps result index -> list of original indices
 
             for name_lower, (entity_data, event_date, indices) in unique_entities.items():
                 entity_names.append(entity_data["text"])
                 entity_dates.append(event_date)
+                entity_counts.append(len(indices))  # Count of occurrences in this batch
                 indices_map.append(indices)
 
             # Batch INSERT ... ON CONFLICT with RETURNING
-            # This is much faster than individual inserts
+            # Uses the batch count for mention_count instead of always 1
             rows = await conn.fetch(
-                """
-                INSERT INTO entities (bank_id, canonical_name, first_seen, last_seen, mention_count)
-                SELECT $1, name, event_date, event_date, 1
-                FROM unnest($2::text[], $3::timestamptz[]) AS t(name, event_date)
+                f"""
+                INSERT INTO {fq_table("entities")} (bank_id, canonical_name, first_seen, last_seen, mention_count)
+                SELECT $1, name, event_date, event_date, cnt
+                FROM unnest($2::text[], $3::timestamptz[], $4::int[]) AS t(name, event_date, cnt)
                 ON CONFLICT (bank_id, LOWER(canonical_name))
                 DO UPDATE SET
-                    mention_count = entities.mention_count + 1,
+                    mention_count = {fq_table("entities")}.mention_count + EXCLUDED.mention_count,
                     last_seen = EXCLUDED.last_seen
                 RETURNING id
                 """,
                 bank_id,
                 entity_names,
                 entity_dates,
+                entity_counts,
             )
 
             # Map returned IDs back to original indices
@@ -279,9 +283,9 @@ class EntityResolver:
         async with acquire_with_retry(self.pool) as conn:
             # Find candidate entities with similar name
             candidates = await conn.fetch(
-                """
+                f"""
                 SELECT id, canonical_name, metadata, last_seen
-                FROM entities
+                FROM {fq_table("entities")}
                 WHERE bank_id = $1
                   AND (
                     canonical_name ILIKE $2
@@ -326,10 +330,10 @@ class EntityResolver:
                 # Get entities that co-occurred with this candidate before
                 # Use the materialized co-occurrence cache for fast lookup
                 co_entity_rows = await conn.fetch(
-                    """
+                    f"""
                     SELECT e.canonical_name, ec.cooccurrence_count
-                    FROM entity_cooccurrences ec
-                    JOIN entities e ON (
+                    FROM {fq_table("entity_cooccurrences")} ec
+                    JOIN {fq_table("entities")} e ON (
                         CASE
                             WHEN ec.entity_id_1 = $1 THEN ec.entity_id_2
                             WHEN ec.entity_id_2 = $1 THEN ec.entity_id_1
@@ -365,8 +369,8 @@ class EntityResolver:
             if best_score > threshold:
                 # Update entity
                 await conn.execute(
-                    """
-                    UPDATE entities
+                    f"""
+                    UPDATE {fq_table("entities")}
                     SET mention_count = mention_count + 1,
                         last_seen = $1
                     WHERE id = $2
@@ -402,12 +406,12 @@ class EntityResolver:
             Entity ID
         """
         entity_id = await conn.fetchval(
-            """
-            INSERT INTO entities (bank_id, canonical_name, first_seen, last_seen, mention_count)
+            f"""
+            INSERT INTO {fq_table("entities")} (bank_id, canonical_name, first_seen, last_seen, mention_count)
             VALUES ($1, $2, $3, $4, 1)
             ON CONFLICT (bank_id, LOWER(canonical_name))
             DO UPDATE SET
-                mention_count = entities.mention_count + 1,
+                mention_count = {fq_table("entities")}.mention_count + 1,
                 last_seen = EXCLUDED.last_seen
             RETURNING id
             """,
@@ -430,8 +434,8 @@ class EntityResolver:
         async with acquire_with_retry(self.pool) as conn:
             # Insert unit-entity link
             await conn.execute(
-                """
-                INSERT INTO unit_entities (unit_id, entity_id)
+                f"""
+                INSERT INTO {fq_table("unit_entities")} (unit_id, entity_id)
                 VALUES ($1, $2)
                 ON CONFLICT DO NOTHING
                 """,
@@ -441,9 +445,9 @@ class EntityResolver:
 
             # Update co-occurrence cache: find other entities in this unit
             rows = await conn.fetch(
-                """
+                f"""
                 SELECT entity_id
-                FROM unit_entities
+                FROM {fq_table("unit_entities")}
                 WHERE unit_id = $1 AND entity_id != $2
                 """,
                 unit_id,
@@ -472,12 +476,12 @@ class EntityResolver:
             entity_id_1, entity_id_2 = entity_id_2, entity_id_1
 
         await conn.execute(
-            """
-            INSERT INTO entity_cooccurrences (entity_id_1, entity_id_2, cooccurrence_count, last_cooccurred)
+            f"""
+            INSERT INTO {fq_table("entity_cooccurrences")} (entity_id_1, entity_id_2, cooccurrence_count, last_cooccurred)
             VALUES ($1, $2, 1, NOW())
             ON CONFLICT (entity_id_1, entity_id_2)
             DO UPDATE SET
-                cooccurrence_count = entity_cooccurrences.cooccurrence_count + 1,
+                cooccurrence_count = {fq_table("entity_cooccurrences")}.cooccurrence_count + 1,
                 last_cooccurred = NOW()
             """,
             entity_id_1,
@@ -506,8 +510,8 @@ class EntityResolver:
     async def _link_units_to_entities_batch_impl(self, conn, unit_entity_pairs: list[tuple[str, str]]):
         # Batch insert all unit-entity links
         await conn.executemany(
-            """
-            INSERT INTO unit_entities (unit_id, entity_id)
+            f"""
+            INSERT INTO {fq_table("unit_entities")} (unit_id, entity_id)
             VALUES ($1, $2)
             ON CONFLICT DO NOTHING
             """,
@@ -541,12 +545,12 @@ class EntityResolver:
         if cooccurrence_pairs:
             now = datetime.now(UTC)
             await conn.executemany(
-                """
-                INSERT INTO entity_cooccurrences (entity_id_1, entity_id_2, cooccurrence_count, last_cooccurred)
+                f"""
+                INSERT INTO {fq_table("entity_cooccurrences")} (entity_id_1, entity_id_2, cooccurrence_count, last_cooccurred)
                 VALUES ($1, $2, $3, $4)
                 ON CONFLICT (entity_id_1, entity_id_2)
                 DO UPDATE SET
-                    cooccurrence_count = entity_cooccurrences.cooccurrence_count + 1,
+                    cooccurrence_count = {fq_table("entity_cooccurrences")}.cooccurrence_count + 1,
                     last_cooccurred = EXCLUDED.last_cooccurred
                 """,
                 [(e1, e2, 1, now) for e1, e2 in cooccurrence_pairs],
@@ -565,9 +569,9 @@ class EntityResolver:
         """
         async with acquire_with_retry(self.pool) as conn:
             rows = await conn.fetch(
-                """
+                f"""
                 SELECT unit_id
-                FROM unit_entities
+                FROM {fq_table("unit_entities")}
                 WHERE entity_id = $1
                 ORDER BY unit_id
                 LIMIT $2
@@ -594,8 +598,8 @@ class EntityResolver:
         """
         async with acquire_with_retry(self.pool) as conn:
             row = await conn.fetchrow(
-                """
-                SELECT id FROM entities
+                f"""
+                SELECT id FROM {fq_table("entities")}
                 WHERE bank_id = $1
                   AND canonical_name ILIKE $2
                 ORDER BY mention_count DESC

hindsight-api/hindsight_api/engine/interface.py

@@ -0,0 +1,619 @@
+"""Abstract interface for MemoryEngine public methods.
+
+This module defines the public API that HTTP endpoints and extensions should use
+to interact with the memory system. All methods require a RequestContext for
+authentication when a TenantExtension is configured.
+"""
+
+from abc import ABC, abstractmethod
+from datetime import datetime
+from typing import TYPE_CHECKING, Any
+
+if TYPE_CHECKING:
+    from hindsight_api.engine.memory_engine import Budget
+    from hindsight_api.engine.response_models import RecallResult, ReflectResult
+    from hindsight_api.models import RequestContext
+
+
+class MemoryEngineInterface(ABC):
+    """
+    Abstract interface for the Memory Engine.
+
+    This defines the public API that should be used by HTTP endpoints and extensions.
+    All methods require a RequestContext for authentication.
+    """
+
+    # =========================================================================
+    # Health & Status
+    # =========================================================================
+
+    @abstractmethod
+    async def health_check(self) -> dict:
+        """
+        Check the health of the memory system.
+
+        Returns:
+            Dict with 'status' key ('healthy' or 'unhealthy') and additional info.
+        """
+        ...
+
+    # =========================================================================
+    # Core Memory Operations
+    # =========================================================================
+
+    @abstractmethod
+    async def retain_batch_async(
+        self,
+        bank_id: str,
+        contents: list[dict[str, Any]],
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        Retain a batch of memory items.
+
+        Args:
+            bank_id: The memory bank ID.
+            contents: List of content dicts with 'content', optional 'event_date',
+                     'context', 'metadata', 'document_id'.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with processing results.
+        """
+        ...
+
+    @abstractmethod
+    async def recall_async(
+        self,
+        bank_id: str,
+        query: str,
+        *,
+        budget: "Budget | None" = None,
+        max_tokens: int = 4096,
+        enable_trace: bool = False,
+        fact_type: list[str] | None = None,
+        question_date: datetime | None = None,
+        include_entities: bool = False,
+        max_entity_tokens: int = 500,
+        include_chunks: bool = False,
+        max_chunk_tokens: int = 8192,
+        request_context: "RequestContext",
+    ) -> "RecallResult":
+        """
+        Recall memories relevant to a query.
+
+        Args:
+            bank_id: The memory bank ID.
+            query: The search query.
+            budget: Search budget (LOW, MID, HIGH).
+            max_tokens: Maximum tokens in response.
+            enable_trace: Include trace information.
+            fact_type: Filter by fact types.
+            question_date: Context date for temporal relevance.
+            include_entities: Include entity observations.
+            max_entity_tokens: Max tokens for entity observations.
+            include_chunks: Include raw chunks.
+            max_chunk_tokens: Max tokens for chunks.
+            request_context: Request context for authentication.
+
+        Returns:
+            RecallResult with matching memories.
+        """
+        ...
+
+    @abstractmethod
+    async def reflect_async(
+        self,
+        bank_id: str,
+        query: str,
+        *,
+        budget: "Budget | None" = None,
+        context: str | None = None,
+        max_tokens: int = 4096,
+        response_schema: dict | None = None,
+        request_context: "RequestContext",
+    ) -> "ReflectResult":
+        """
+        Reflect on a query and generate a thoughtful response.
+
+        Args:
+            bank_id: The memory bank ID.
+            query: The question to reflect on.
+            budget: Search budget for retrieving context.
+            context: Additional context for the reflection.
+            max_tokens: Maximum tokens for the response.
+            response_schema: Optional JSON Schema for structured output.
+            request_context: Request context for authentication.
+
+        Returns:
+            ReflectResult with generated response and supporting facts.
+        """
+        ...
+
+    # =========================================================================
+    # Bank Management
+    # =========================================================================
+
+    @abstractmethod
+    async def list_banks(
+        self,
+        *,
+        request_context: "RequestContext",
+    ) -> list[dict[str, Any]]:
+        """
+        List all memory banks.
+
+        Args:
+            request_context: Request context for authentication.
+
+        Returns:
+            List of bank info dicts.
+        """
+        ...
+
+    @abstractmethod
+    async def get_bank_profile(
+        self,
+        bank_id: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        Get bank profile including disposition and mission.
+
+        Args:
+            bank_id: The memory bank ID.
+            request_context: Request context for authentication.
+
+        Returns:
+            Bank profile dict with bank_id, name, disposition, and mission.
+        """
+        ...
+
+    @abstractmethod
+    async def update_bank_disposition(
+        self,
+        bank_id: str,
+        disposition: dict[str, int],
+        *,
+        request_context: "RequestContext",
+    ) -> None:
+        """
+        Update bank disposition traits.
+
+        Args:
+            bank_id: The memory bank ID.
+            disposition: Dict with trait values.
+            request_context: Request context for authentication.
+        """
+        ...
+
+    @abstractmethod
+    async def merge_bank_mission(
+        self,
+        bank_id: str,
+        new_info: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        Merge new mission information into bank profile.
+
+        Args:
+            bank_id: The memory bank ID.
+            new_info: New mission information to merge.
+            request_context: Request context for authentication.
+
+        Returns:
+            Updated mission info.
+        """
+        ...
+
+    @abstractmethod
+    async def set_bank_mission(
+        self,
+        bank_id: str,
+        mission: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        Set the bank's mission (replaces existing).
+
+        Args:
+            bank_id: The memory bank ID.
+            mission: The mission text.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with bank_id and mission.
+        """
+        ...
+
+    @abstractmethod
+    async def delete_bank(
+        self,
+        bank_id: str,
+        *,
+        fact_type: str | None = None,
+        request_context: "RequestContext",
+    ) -> dict[str, int]:
+        """
+        Delete a bank or its memories.
+
+        Args:
+            bank_id: The memory bank ID.
+            fact_type: If specified, only delete memories of this type.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with deletion counts.
+        """
+        ...
+
+    # =========================================================================
+    # Memory Units
+    # =========================================================================
+
+    @abstractmethod
+    async def list_memory_units(
+        self,
+        bank_id: str,
+        *,
+        fact_type: str | None = None,
+        search_query: str | None = None,
+        limit: int = 100,
+        offset: int = 0,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        List memory units with pagination.
+
+        Args:
+            bank_id: The memory bank ID.
+            fact_type: Filter by fact type.
+            search_query: Full-text search query.
+            limit: Maximum results.
+            offset: Pagination offset.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with 'items', 'total', 'limit', 'offset'.
+        """
+        ...
+
+    @abstractmethod
+    async def delete_memory_unit(
+        self,
+        unit_id: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        Delete a specific memory unit.
+
+        Args:
+            unit_id: The memory unit ID.
+            request_context: Request context for authentication.
+
+        Returns:
+            Deletion result.
+        """
+        ...
+
+    @abstractmethod
+    async def get_graph_data(
+        self,
+        bank_id: str,
+        *,
+        fact_type: str | None = None,
+        limit: int = 1000,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        Get graph data for visualization.
+
+        Args:
+            bank_id: The memory bank ID.
+            fact_type: Filter by fact type.
+            limit: Maximum number of items to return (default: 1000).
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with nodes, edges, table_rows, total_units, limit.
+        """
+        ...
+
+    # =========================================================================
+    # Documents
+    # =========================================================================
+
+    @abstractmethod
+    async def list_documents(
+        self,
+        bank_id: str,
+        *,
+        search_query: str | None = None,
+        limit: int = 100,
+        offset: int = 0,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        List documents with pagination.
+
+        Args:
+            bank_id: The memory bank ID.
+            search_query: Search query.
+            limit: Maximum results.
+            offset: Pagination offset.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with 'items', 'total', 'limit', 'offset'.
+        """
+        ...
+
+    @abstractmethod
+    async def get_document(
+        self,
+        document_id: str,
+        bank_id: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any] | None:
+        """
+        Get a specific document.
+
+        Args:
+            document_id: The document ID.
+            bank_id: The memory bank ID.
+            request_context: Request context for authentication.
+
+        Returns:
+            Document dict or None if not found.
+        """
+        ...
+
+    @abstractmethod
+    async def delete_document(
+        self,
+        document_id: str,
+        bank_id: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, int]:
+        """
+        Delete a document and its memory units.
+
+        Args:
+            document_id: The document ID.
+            bank_id: The memory bank ID.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with deletion counts.
+        """
+        ...
+
+    @abstractmethod
+    async def get_chunk(
+        self,
+        chunk_id: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any] | None:
+        """
+        Get a specific chunk.
+
+        Args:
+            chunk_id: The chunk ID.
+            request_context: Request context for authentication.
+
+        Returns:
+            Chunk dict or None if not found.
+        """
+        ...
+
+    # =========================================================================
+    # Entities
+    # =========================================================================
+
+    @abstractmethod
+    async def list_entities(
+        self,
+        bank_id: str,
+        *,
+        limit: int = 100,
+        offset: int = 0,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        List entities for a bank with pagination.
+
+        Args:
+            bank_id: The memory bank ID.
+            limit: Maximum results.
+            offset: Offset for pagination.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with items, total, limit, offset.
+        """
+        ...
+
+    @abstractmethod
+    async def get_entity_observations(
+        self,
+        bank_id: str,
+        entity_id: str,
+        *,
+        limit: int = 10,
+        request_context: "RequestContext",
+    ) -> list[Any]:
+        """
+        Get observations for an entity.
+
+        Args:
+            bank_id: The memory bank ID.
+            entity_id: The entity ID.
+            limit: Maximum observations.
+            request_context: Request context for authentication.
+
+        Returns:
+            List of EntityObservation objects.
+        """
+        ...
+
+    @abstractmethod
+    async def regenerate_entity_observations(
+        self,
+        bank_id: str,
+        entity_id: str,
+        entity_name: str,
+        *,
+        request_context: "RequestContext",
+    ) -> None:
+        """
+        Regenerate observations for an entity.
+
+        Args:
+            bank_id: The memory bank ID.
+            entity_id: The entity ID.
+            entity_name: The entity's canonical name.
+            request_context: Request context for authentication.
+        """
+        ...
+
+    # =========================================================================
+    # Statistics & Operations
+    # =========================================================================
+
+    @abstractmethod
+    async def get_bank_stats(
+        self,
+        bank_id: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        Get statistics about memory nodes and links for a bank.
+
+        Args:
+            bank_id: The memory bank ID.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with node_counts, link_counts, link_counts_by_fact_type,
+            link_breakdown, and operations stats.
+        """
+        ...
+
+    @abstractmethod
+    async def get_entity(
+        self,
+        bank_id: str,
+        entity_id: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any] | None:
+        """
+        Get entity details including metadata and observations.
+
+        Args:
+            bank_id: The memory bank ID.
+            entity_id: The entity ID.
+            request_context: Request context for authentication.
+
+        Returns:
+            Entity dict with id, canonical_name, mention_count, first_seen,
+            last_seen, metadata, and observations. None if not found.
+        """
+        ...
+
+    @abstractmethod
+    async def list_operations(
+        self,
+        bank_id: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        List async operations for a bank.
+
+        Args:
+            bank_id: The memory bank ID.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with 'total' (int) and 'operations' (list of operation dicts).
+        """
+        ...
+
+    @abstractmethod
+    async def cancel_operation(
+        self,
+        bank_id: str,
+        operation_id: str,
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        Cancel a pending async operation.
+
+        Args:
+            bank_id: The memory bank ID.
+            operation_id: The operation ID to cancel.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with success status and message.
+
+        Raises:
+            ValueError: If operation not found.
+        """
+        ...
+
+    @abstractmethod
+    async def update_bank(
+        self,
+        bank_id: str,
+        *,
+        name: str | None = None,
+        mission: str | None = None,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        Update bank name and/or mission.
+
+        Args:
+            bank_id: The memory bank ID.
+            name: New bank name (optional).
+            mission: New mission text (optional, replaces existing).
+            request_context: Request context for authentication.
+
+        Returns:
+            Updated bank profile dict.
+        """
+        ...
+
+    @abstractmethod
+    async def submit_async_retain(
+        self,
+        bank_id: str,
+        contents: list[dict[str, Any]],
+        *,
+        request_context: "RequestContext",
+    ) -> dict[str, Any]:
+        """
+        Submit a batch retain operation to run asynchronously.
+
+        Args:
+            bank_id: The memory bank ID.
+            contents: List of content dicts to retain.
+            request_context: Request context for authentication.
+
+        Returns:
+            Dict with operation_id and items_count.
+        """
+        ...

hindsight-api/hindsight_api/engine/mental_models/__init__.py

@@ -0,0 +1,18 @@
+"""
+Mental models module for Hindsight.
+
+Mental models are synthesized summaries that represent understanding. They come
+in different subtypes based on how they were created:
+
+- Structural: Derived from the bank's mission (e.g., "Be a PM for engineering team")
+  These are created upfront based on what any agent with this role would need.
+
+- Emergent: Discovered from data patterns (named entities, temporal clusters, etc.)
+  These surface organically as facts are retained.
+
+- Pinned: User-defined models that persist across refreshes.
+"""
+
+from .models import MentalModel, MentalModelSubtype
+
+__all__ = ["MentalModel", "MentalModelSubtype"]

hindsight-api/hindsight_api/engine/mental_models/emergent.py

@@ -0,0 +1,311 @@
+"""
+Emergent mental model detection and promotion.
+
+Emergent models are discovered from data patterns:
+- Named entity extraction (people, projects, systems)
+- Temporal clustering (events with multiple references)
+- Causal patterns ("Because X, we do Y")
+- Behavioral anchors ("After X, we started Y")
+- Reference frequency (anything mentioned repeatedly)
+
+When a pattern is detected, it goes through a mission filter to check relevance,
+and if relevant, is promoted to a mental model.
+"""
+
+import logging
+from typing import TYPE_CHECKING
+
+from pydantic import BaseModel, Field
+
+from .models import EmergentCandidate
+
+if TYPE_CHECKING:
+    from ..llm_wrapper import LLMConfig
+
+logger = logging.getLogger(__name__)
+
+
+class MissionFilterCandidate(BaseModel):
+    """Result of mission filtering for a single candidate."""
+
+    name: str
+    promote: bool = Field(description="True if this is a specific named entity worth tracking")
+    reason: str = Field(description="Brief explanation for the decision")
+
+
+class MissionFilterResponse(BaseModel):
+    """Response from LLM for mission filtering."""
+
+    candidates: list[MissionFilterCandidate] = Field(description="Filtering decision for each candidate")
+
+
+def build_mission_filter_prompt(mission: str, candidates: list[EmergentCandidate]) -> str:
+    """Build the prompt for filtering candidates by mission relevance."""
+    candidate_list = "\n".join(
+        [f"- {c.name} (mentions: {c.mention_count}, method: {c.detection_method})" for c in candidates]
+    )
+
+    return f"""Filter these detected entities. For each one, decide: promote=true or promote=false.
+
+MISSION: {mission}
+
+DETECTED ENTITIES:
+{candidate_list}
+
+=== DECISION RULES ===
+
+Set promote=true ONLY for specific, named entities:
+- Person names: "John", "Maria", "Alice Chen", "Dr. Smith"
+- Named organizations: "Google", "Acme Corp", "Frontend Team"
+- Named places: "Central Park Zoo", "NYC Office", "Building A"
+- Named projects: "Project Phoenix", "Auth Service v2"
+
+Set promote=false for EVERYTHING ELSE, including:
+- Common English words: user, support, help, family, kids, parents, friends, people, team, photo, nature, park, office, home, work, school, joy, love, hope, fear, anger, gratitude, kindness, passion, motivation, inspiration, encouragement, positivity, energy, community, connection, commitment, collaboration, growth, impact, difference, success, progress, change, education, volunteering, veterans, homeless, shelter, meeting, project, system, process, event
+- Generic categories (even capitalized): Users, Customers, Team, Family, Kids, Veterans, Community
+- Abstract concepts: motivation, inspiration, gratitude, commitment, resilience
+
+THE TEST: Is this a specific name you'd find in a contact list or org chart?
+- "John" → YES (promote=true)
+- "kids" → NO (promote=false)
+- "community" → NO (promote=false)
+- "Maria" → YES (promote=true)
+- "park" → NO (promote=false)
+
+When in doubt, set promote=false."""
+
+
+def get_mission_filter_system_message() -> str:
+    """System message for mission filtering."""
+    return """You filter entities for promotion. Output JSON with 'candidates' array.
+
+Rules:
+- promote=true ONLY for specific names (people, organizations, named places/projects)
+- promote=false for common words, generic categories, abstract concepts
+
+Examples:
+- "John" → promote=true (person name)
+- "kids" → promote=false (generic category)
+- "community" → promote=false (abstract concept)
+- "Google" → promote=true (organization name)
+- "motivation" → promote=false (abstract concept)
+
+When in doubt, promote=false. Most entities should be rejected."""
+
+
+async def filter_candidates_by_mission(
+    llm_config: "LLMConfig",
+    mission: str,
+    candidates: list[EmergentCandidate],
+) -> list[EmergentCandidate]:
+    """
+    Filter emergent candidates to keep only specific, named entities.
+
+    Args:
+        llm_config: LLM configuration
+        mission: The bank's mission (used for context)
+        candidates: List of detected candidates
+
+    Returns:
+        Filtered list of candidates that are specific named entities
+    """
+    if not candidates:
+        return []
+
+    if not mission:
+        # No mission = no filtering, keep all candidates
+        logger.debug("[EMERGENT] No mission set, skipping filter")
+        return candidates
+
+    prompt = build_mission_filter_prompt(mission, candidates)
+
+    try:
+        result = await llm_config.call(
+            messages=[
+                {"role": "system", "content": get_mission_filter_system_message()},
+                {"role": "user", "content": prompt},
+            ],
+            response_format=MissionFilterResponse,
+            scope="mental_model_mission_filter",
+        )
+
+        # Build name -> promote map
+        promote_map = {c.name: c.promote for c in result.candidates}
+
+        # Filter candidates
+        filtered = []
+        for candidate in candidates:
+            if candidate.name in promote_map:
+                if promote_map[candidate.name]:
+                    filtered.append(candidate)
+                    logger.debug(f"[EMERGENT] Promoting '{candidate.name}'")
+                else:
+                    logger.debug(f"[EMERGENT] Rejecting '{candidate.name}'")
+            else:
+                # Candidate not in response - reject by default
+                logger.debug(f"[EMERGENT] '{candidate.name}' not in response, rejecting")
+
+        logger.info(f"[EMERGENT] Mission filter: {len(filtered)}/{len(candidates)} candidates promoted")
+        return filtered
+
+    except Exception as e:
+        logger.warning(f"[EMERGENT] Mission filter failed, rejecting all candidates: {e}")
+        return []
+
+
+async def evaluate_emergent_models(
+    llm_config: "LLMConfig",
+    models: list[dict],
+) -> list[str]:
+    """
+    Evaluate existing emergent models to check if they should be kept.
+
+    This re-evaluates emergent models using the same filtering criteria
+    as new candidates. Models that are generic/abstract will be removed.
+
+    Args:
+        llm_config: LLM configuration
+        models: List of existing emergent model dicts with 'name', 'id'
+
+    Returns:
+        List of model IDs that should be REMOVED (no longer valid)
+    """
+    if not models:
+        return []
+
+    # Convert existing models to candidates for evaluation
+    candidates = [
+        EmergentCandidate(
+            name=m["name"],
+            detection_method="existing_emergent_model",
+            mention_count=0,
+        )
+        for m in models
+    ]
+
+    # Build a simple prompt for re-evaluation
+    names_list = "\n".join([f"- {m['name']}" for m in models])
+    prompt = f"""Re-evaluate these existing mental models. For each one, decide: promote=true (keep) or promote=false (remove).
+
+EXISTING MODELS:
+{names_list}
+
+=== DECISION RULES ===
+
+Set promote=true ONLY for specific, named entities:
+- Person names: "John", "Maria", "Alice Chen", "Dr. Smith"
+- Named organizations: "Google", "Acme Corp", "Frontend Team"
+- Named places: "Central Park Zoo", "NYC Office", "Building A"
+- Named projects: "Project Phoenix", "Auth Service v2"
+
+Set promote=false for EVERYTHING ELSE, including:
+- Common English words: user, support, help, family, kids, parents, friends, people, team, photo, nature, park, office, home, work, school, joy, love, hope, fear, anger, gratitude, kindness, passion, motivation, inspiration, encouragement, positivity, energy, community, connection, commitment, collaboration, growth, impact, difference, success, progress, change, education, volunteering, veterans, homeless, shelter, meeting, project, system, process, event
+- Generic categories (even capitalized): Users, Customers, Team, Family, Kids, Veterans, Community
+- Abstract concepts: motivation, inspiration, gratitude, commitment, resilience
+
+THE TEST: Is this a specific name you'd find in a contact list or org chart?
+- "John" → YES (promote=true)
+- "kids" → NO (promote=false)
+- "community" → NO (promote=false)
+
+When in doubt, set promote=false."""
+
+    try:
+        result = await llm_config.call(
+            messages=[
+                {"role": "system", "content": get_mission_filter_system_message()},
+                {"role": "user", "content": prompt},
+            ],
+            response_format=MissionFilterResponse,
+            scope="mental_model_emergent_evaluation",
+        )
+
+        # Build name -> promote map
+        promote_map = {c.name: c.promote for c in result.candidates}
+
+        # Find models to remove
+        models_to_remove = []
+        for model in models:
+            name = model["name"]
+            if name in promote_map:
+                if not promote_map[name]:
+                    models_to_remove.append(model["id"])
+                else:
+                    logger.debug(f"[EMERGENT] Keeping '{name}'")
+            else:
+                # Model not in response - remove to be safe
+                logger.info(f"[EMERGENT] '{name}' not in evaluation response, marking for removal")
+                models_to_remove.append(model["id"])
+
+        logger.info(f"[EMERGENT] Evaluation: {len(models_to_remove)}/{len(models)} emergent models marked for removal")
+        return models_to_remove
+
+    except Exception as e:
+        logger.warning(f"[EMERGENT] Evaluation failed, keeping all models: {e}")
+        return []
+
+
+async def detect_entity_candidates(
+    pool,
+    bank_id: str,
+    min_mentions: int = 5,
+    top_percent: int = 20,
+) -> list[EmergentCandidate]:
+    """
+    Detect entities that are candidates for promotion to mental models.
+
+    Args:
+        pool: Database connection pool
+        bank_id: Bank identifier
+        min_mentions: Minimum mention count to consider
+        top_percent: Only consider top X% by mention count
+
+    Returns:
+        List of entity candidates
+    """
+    from ..db_utils import acquire_with_retry
+    from ..memory_engine import fq_table
+
+    candidates = []
+
+    async with acquire_with_retry(pool) as conn:
+        # Get entities that meet criteria and don't already have mental models
+        rows = await conn.fetch(
+            f"""
+            WITH ranked AS (
+                SELECT
+                    e.id,
+                    e.canonical_name,
+                    e.mention_count,
+                    PERCENT_RANK() OVER (ORDER BY e.mention_count DESC) as rank_pct
+                FROM {fq_table("entities")} e
+                LEFT JOIN {fq_table("mental_models")} mm
+                    ON mm.entity_id = e.id AND mm.bank_id = e.bank_id
+                WHERE e.bank_id = $1
+                  AND e.mention_count >= $2
+                  AND mm.id IS NULL  -- Not already a mental model
+            )
+            SELECT id, canonical_name, mention_count
+            FROM ranked
+            WHERE rank_pct <= $3
+            ORDER BY mention_count DESC
+            LIMIT 50
+            """,
+            bank_id,
+            min_mentions,
+            top_percent / 100.0,
+        )
+
+        for row in rows:
+            candidates.append(
+                EmergentCandidate(
+                    name=row["canonical_name"],
+                    detection_method="named_entity_extraction",
+                    mention_count=row["mention_count"],
+                    entity_id=str(row["id"]),
+                    relevance_score=0.0,
+                )
+            )
+
+    logger.debug(f"[EMERGENT] Detected {len(candidates)} entity candidates")
+    return candidates

hindsight-api/hindsight_api/engine/mental_models/models.py

@@ -0,0 +1,97 @@
+"""
+Pydantic models for mental models.
+"""
+
+from datetime import datetime, timezone
+from enum import Enum
+
+from pydantic import BaseModel, Field
+
+
+class MentalModelSubtype(str, Enum):
+    """Subtype of mental model - how it was created."""
+
+    STRUCTURAL = "structural"  # Derived from mission, created upfront
+    EMERGENT = "emergent"  # Discovered from data patterns
+    LEARNED = "learned"  # Formed through reflection
+    PINNED = "pinned"  # User-defined, persists across refreshes
+
+
+class MentalModel(BaseModel):
+    """
+    A mental model representing synthesized understanding.
+
+    Mental models are the agent's consolidated knowledge. Unlike raw facts,
+    mental models provide:
+    - A one-liner description for quick scanning/retrieval
+    - A full summary for deep understanding
+    - Links to related mental models
+    """
+
+    id: str = Field(description="Unique identifier within the bank")
+    bank_id: str = Field(description="Bank this mental model belongs to")
+    subtype: MentalModelSubtype = Field(description="How this model was created")
+    name: str = Field(description="Human-readable name")
+    description: str = Field(description="One-liner for quick scanning and retrieval matching")
+    summary: str | None = Field(default=None, description="Full synthesized understanding")
+
+    # References
+    entity_id: str | None = Field(default=None, description="Reference to entities table when type=entity")
+    source_facts: list[str] = Field(default_factory=list, description="Fact IDs used to generate summary")
+    links: list[str] = Field(default_factory=list, description="Related mental model IDs")
+
+    # Tags for scoped visibility (similar to document tags)
+    tags: list[str] = Field(default_factory=list, description="Tags for scoped visibility filtering")
+
+    # Timestamps
+    last_updated: datetime | None = Field(default=None, description="When summary was last regenerated")
+    created_at: datetime = Field(
+        default_factory=lambda: datetime.now(timezone.utc), description="When this model was created"
+    )
+
+
+class StructuralModelTemplate(BaseModel):
+    """
+    A template for a structural mental model.
+
+    Generated by LLM based on the bank's mission. Represents what any agent
+    with this role would need to track.
+    """
+
+    id: str = Field(default="", description="Existing model ID to keep, or empty for new models")
+    name: str = Field(description="Human-readable name")
+    description: str = Field(description="What this model should track")
+    initial_probes: list[str] = Field(default_factory=list, description="Initial search queries to populate this model")
+
+
+class StructuralModelDerivationResponse(BaseModel):
+    """Response from LLM for structural model derivation."""
+
+    templates: list[StructuralModelTemplate] = Field(description="Structural model templates derived from the mission")
+
+
+class EmergentCandidate(BaseModel):
+    """
+    A candidate for promotion to emergent mental model.
+
+    Detected through pattern analysis of facts.
+    """
+
+    name: str = Field(description="Name of the detected pattern/entity")
+    detection_method: str = Field(description="How this candidate was detected")
+    mention_count: int = Field(default=0, description="How many times referenced")
+    entity_id: str | None = Field(default=None, description="Entity ID if detected as entity")
+    relevance_score: float = Field(default=0.0, description="Score from mission filter (0-1)")
+
+
+class ResearchResult(BaseModel):
+    """
+    Result from the research endpoint.
+
+    Contains the answer along with the mental models and facts used.
+    """
+
+    answer: str = Field(description="The synthesized answer")
+    mental_models_used: list[str] = Field(default_factory=list, description="IDs of mental models that contributed")
+    facts_used: list[str] = Field(default_factory=list, description="Fact IDs that contributed")
+    question_type: str | None = Field(default=None, description="Detected question type (WHO, WHAT, HOW, etc.)")

hindsight-api/hindsight_api/engine/mental_models/structural.py

@@ -0,0 +1,228 @@
+"""
+Structural mental model derivation from bank mission.
+
+Structural models are derived from the bank's mission - they represent what
+any agent with this role would need to track. For example:
+
+Mission: "Be a PM for engineering team"
+Structural models:
+  - Team Structure (who's on the team, roles)
+  - Project Overview (current projects, status)
+  - Processes (how releases work, how decisions are made)
+  - Key Systems (what we own, dependencies)
+"""
+
+import logging
+from typing import TYPE_CHECKING
+
+from pydantic import BaseModel, Field
+
+from .models import StructuralModelTemplate
+
+if TYPE_CHECKING:
+    from ..llm_wrapper import LLMConfig
+
+logger = logging.getLogger(__name__)
+
+
+class StructuralDerivationResponse(BaseModel):
+    """Response from LLM for structural model derivation."""
+
+    templates: list[StructuralModelTemplate] = Field(description="Structural model templates derived from the mission")
+
+
+class StructuralRelevanceResult(BaseModel):
+    """Result of evaluating a structural model's relevance to the mission."""
+
+    name: str
+    relevant: bool
+    reason: str
+
+
+class StructuralRelevanceResponse(BaseModel):
+    """Response from LLM for structural model relevance evaluation."""
+
+    models: list[StructuralRelevanceResult] = Field(description="Relevance evaluation for each model")
+
+
+def build_structural_derivation_prompt(mission: str, existing_models: list[dict] | None = None) -> str:
+    """Build the prompt for deriving structural models from a mission."""
+    existing_section = ""
+    if existing_models:
+        model_list = "\n".join([f"- id='{m['id']}' name='{m['name']}': {m['description']}" for m in existing_models])
+        existing_section = f"""
+EXISTING STRUCTURAL MODELS:
+{model_list}
+
+IMPORTANT: If keeping an existing model, you MUST return its EXACT 'id' value.
+Models not included in your output will be REMOVED.
+"""
+
+    return f"""Given this agent mission, identify the KEY THINGS to track to achieve it.
+
+MISSION: {mission}
+{existing_section}
+IMPORTANT CONSTRAINTS:
+- Return 0-3 structural models MAXIMUM (less is better!)
+- Only include models for SPECIFIC, CONCRETE things the agent needs to track
+- Each model must be DIRECTLY tied to achieving the mission
+- If the mission is simple, return 0 models (empty array is fine)
+- If existing models are provided and you want to keep one, use its EXACT id
+- Do NOT create near-duplicates (e.g., don't create "topic-map" if "topic-connections" exists)
+
+GOOD examples (specific, actionable):
+- Mission: "Be a PM for engineering team" → "Team Members" (track who's on the team)
+- Mission: "Track customer feedback" → "Customer Issues" (track specific complaints/requests)
+- Mission: "Manage project X" → "Project X Milestones" (track progress)
+
+BAD examples (too generic, don't create these):
+- "Processes", "Workflows", "Key Systems", "Important Events"
+- "Communication", "Collaboration", "Progress", "Status"
+- Generic role-based models not tied to the specific mission
+
+For each model:
+1. id: Use EXACT existing id if keeping a model, or leave empty for new models
+2. name: Short, specific name (e.g., "Team Members", "Sprint Goals")
+3. description: One line describing what to track
+4. initial_probes: 2-3 search queries to find relevant information
+
+Return ONLY the models that should exist. Existing models not in your output will be deleted."""
+
+
+def get_structural_derivation_system_message() -> str:
+    """System message for structural model derivation."""
+    return """You identify the key things to track for a mission. Be VERY selective.
+
+Rules:
+- Maximum 3 models (prefer fewer)
+- Only SPECIFIC, CONCRETE things - not generic categories
+- Each must DIRECTLY help achieve the mission
+- Empty array is valid if no models are truly needed
+- If existing models are shown and you want to keep one, return its EXACT id
+- Never create duplicates - if a similar model exists, keep the existing one
+
+Output JSON with 'templates' array (can be empty)."""
+
+
+def _normalize_id(text: str) -> str:
+    """Normalize a string to a canonical form for comparison.
+
+    Removes common suffixes, pluralization, and normalizes separators.
+    """
+    # Lowercase and normalize separators
+    normalized = text.lower().replace(" ", "-").replace("_", "-")
+
+    # Remove common suffixes that indicate the same concept
+    suffixes_to_remove = ["-map", "-list", "-overview", "-tracker", "-s"]
+    for suffix in suffixes_to_remove:
+        if normalized.endswith(suffix) and len(normalized) > len(suffix):
+            normalized = normalized[: -len(suffix)]
+
+    return normalized
+
+
+def _find_similar_existing_id(new_id: str, existing_models: list[dict]) -> str | None:
+    """Find an existing model ID that is similar to the new ID.
+
+    Returns the existing ID if a similar one is found, None otherwise.
+    """
+    if not existing_models:
+        return None
+
+    new_normalized = _normalize_id(new_id)
+
+    for model in existing_models:
+        existing_id = model.get("id", "")
+        existing_normalized = _normalize_id(existing_id)
+
+        # Check if one is a prefix of the other (normalized)
+        if new_normalized.startswith(existing_normalized) or existing_normalized.startswith(new_normalized):
+            return existing_id
+
+        # Check if they're the same when normalized
+        if new_normalized == existing_normalized:
+            return existing_id
+
+    return None
+
+
+async def derive_structural_models(
+    llm_config: "LLMConfig",
+    mission: str,
+    existing_models: list[dict] | None = None,
+) -> tuple[list[StructuralModelTemplate], list[str]]:
+    """
+    Derive structural model templates from a bank's mission.
+
+    This combines derivation and evaluation in one call. The LLM sees existing
+    models and decides which to keep. Any existing model not in the output
+    will be marked for removal.
+
+    Args:
+        llm_config: LLM configuration for calling the model
+        mission: The bank's mission (e.g., "Be a PM for engineering team")
+        existing_models: Optional list of existing model dicts with 'name', 'description', 'id'
+
+    Returns:
+        Tuple of (templates to create/keep, IDs of existing models to remove)
+
+    Raises:
+        Exception: If LLM call fails
+    """
+    prompt = build_structural_derivation_prompt(mission, existing_models)
+
+    result = await llm_config.call(
+        messages=[
+            {"role": "system", "content": get_structural_derivation_system_message()},
+            {"role": "user", "content": prompt},
+        ],
+        response_format=StructuralDerivationResponse,
+        scope="mental_model_structural_derivation",
+    )
+
+    templates = result.templates
+    logger.info(f"[STRUCTURAL] LLM returned {len(templates)} structural models")
+
+    # Build set of existing IDs for quick lookup
+    existing_ids = {m["id"] for m in existing_models} if existing_models else set()
+
+    # Process templates: validate IDs, deduplicate, assign stable IDs
+    processed_templates: list[StructuralModelTemplate] = []
+    kept_existing_ids: set[str] = set()
+
+    for template in templates:
+        # If LLM returned an ID, check if it's a valid existing ID
+        if template.id and template.id in existing_ids:
+            # LLM is keeping an existing model
+            kept_existing_ids.add(template.id)
+            processed_templates.append(template)
+            logger.info(f"[STRUCTURAL] Keeping existing model: {template.id}")
+        else:
+            # New model or LLM didn't return a valid ID
+            # Generate ID from name
+            generated_id = template.name.lower().replace(" ", "-").replace("_", "-")
+
+            # Check for similar existing models to prevent near-duplicates
+            similar_id = _find_similar_existing_id(generated_id, existing_models)
+            if similar_id and similar_id not in kept_existing_ids:
+                # Use the existing similar model instead of creating a new one
+                logger.info(f"[STRUCTURAL] Detected near-duplicate: '{generated_id}' matches existing '{similar_id}'")
+                template.id = similar_id
+                kept_existing_ids.add(similar_id)
+            else:
+                template.id = generated_id
+
+            processed_templates.append(template)
+
+    # Find existing models to remove (not kept in LLM output)
+    models_to_remove = []
+    if existing_models:
+        for model in existing_models:
+            if model["id"] not in kept_existing_ids:
+                logger.info(f"[STRUCTURAL] Marking '{model['name']}' (id={model['id']}) for removal")
+                models_to_remove.append(model["id"])
+
+    if models_to_remove:
+        logger.info(f"[STRUCTURAL] {len(models_to_remove)} existing models will be removed")
+
+    return processed_templates, models_to_remove

hindsight-api/hindsight_api/engine/query_analyzer.py

@@ -84,7 +84,7 @@ class DateparserQueryAnalyzer(QueryAnalyzer):
 
     Performance:
     - ~10-50ms per query
-    - No model loading required
+    - No model loading required (lazy import on first use)
     """
 
     def __init__(self):
@@ -112,8 +112,6 @@ class DateparserQueryAnalyzer(QueryAnalyzer):
         Returns:
             QueryAnalysis with temporal_constraint if found
         """
-        self.load()
-
         if reference_date is None:
             reference_date = datetime.now()
 
@@ -123,6 +121,9 @@ class DateparserQueryAnalyzer(QueryAnalyzer):
         if period_result is not None:
             return QueryAnalysis(temporal_constraint=period_result)
 
+        # Lazy load dateparser (only imports on first call, then cached)
+        self.load()
+
         # Use dateparser's search_dates to find temporal expressions
         settings = {
             "RELATIVE_BASE": reference_date,

hindsight-api/hindsight_api/engine/reflect/__init__.py

@@ -0,0 +1,20 @@
+"""
+Reflect agent module for agentic reflection with tools.
+
+The reflect agent uses an iterative loop with tools to:
+1. Lookup mental models (existing knowledge)
+2. Recall facts (semantic + temporal search)
+3. Learn new insights (create/update mental models)
+4. Expand memories (get chunk/document context)
+"""
+
+from .agent import ReflectAgentResult, run_reflect_agent
+from .models import MentalModelInput, ReflectAction, ReflectActionBatch
+
+__all__ = [
+    "run_reflect_agent",
+    "ReflectAgentResult",
+    "ReflectAction",
+    "ReflectActionBatch",
+    "MentalModelInput",
+]

hindsight-api/hindsight_api/engine/reflect/agent.py

@@ -0,0 +1,731 @@
+"""
+Reflect agent - agentic loop for reflection with native tool calling.
+"""
+
+import asyncio
+import json
+import logging
+import time
+from typing import TYPE_CHECKING, Any, Awaitable, Callable, Literal
+
+from .models import LLMCall, MentalModelInput, Observation, ReflectAgentResult, ToolCall
+from .prompts import FINAL_SYSTEM_PROMPT, build_final_prompt, build_system_prompt_for_tools
+from .tools_schema import get_reflect_tools
+
+if TYPE_CHECKING:
+    from ..llm_wrapper import LLMProvider
+    from ..response_models import LLMToolCall
+
+logger = logging.getLogger(__name__)
+
+DEFAULT_MAX_ITERATIONS = 10
+
+
+async def _generate_structured_output(
+    answer: str,
+    response_schema: dict,
+    llm_config: "LLMProvider",
+    reflect_id: str,
+) -> dict[str, Any] | None:
+    """Generate structured output from an answer using the provided JSON schema.
+
+    Args:
+        answer: The text answer to extract structured data from
+        response_schema: JSON Schema for the expected output structure
+        llm_config: LLM provider for making the extraction call
+        reflect_id: Reflect ID for logging
+
+    Returns:
+        Structured output dict if successful, None otherwise
+    """
+    try:
+        from typing import Any as TypingAny
+
+        from pydantic import create_model
+
+        def _json_schema_type_to_python(field_schema: dict) -> type:
+            """Map JSON schema type to Python type for better LLM guidance."""
+            json_type = field_schema.get("type", "string")
+            if json_type == "array":
+                return list
+            elif json_type == "object":
+                return dict
+            elif json_type == "integer":
+                return int
+            elif json_type == "number":
+                return float
+            elif json_type == "boolean":
+                return bool
+            else:
+                return str
+
+        # Build fields from JSON schema properties
+        schema_props = response_schema.get("properties", {})
+        required_fields = set(response_schema.get("required", []))
+        fields: dict[str, TypingAny] = {}
+        for field_name, field_schema in schema_props.items():
+            field_type = _json_schema_type_to_python(field_schema)
+            default = ... if field_name in required_fields else None
+            fields[field_name] = (field_type, default)
+
+        if not fields:
+            return None
+
+        DynamicModel = create_model("StructuredResponse", **fields)
+
+        # Include the full schema in the prompt for better LLM guidance
+        schema_str = json.dumps(response_schema, indent=2)
+
+        # Call LLM with the answer to extract structured data
+        structured_prompt = f"""Based on this answer, extract the information into the requested structured format.
+
+Answer: {answer}
+
+JSON Schema to follow:
+```json
+{schema_str}
+```
+
+Return ONLY a valid JSON object that matches this exact schema. Pay special attention to field types:
+- "type": "array" means the value must be a JSON array/list, NOT a string
+- "type": "string" means the value must be a string
+- "type": "object" means the value must be a JSON object
+
+Do not include any explanation, only the JSON object."""
+
+        structured_result = await llm_config.call(
+            messages=[
+                {
+                    "role": "system",
+                    "content": "Extract structured data from the given answer. Return only valid JSON matching the provided schema exactly.",
+                },
+                {"role": "user", "content": structured_prompt},
+            ],
+            response_format=DynamicModel,
+            scope="reflect_structured",
+            skip_validation=True,  # We'll handle the dict ourselves
+        )
+
+        # Convert to dict
+        if hasattr(structured_result, "model_dump"):
+            structured_output = structured_result.model_dump()
+        elif isinstance(structured_result, dict):
+            structured_output = structured_result
+        else:
+            # Try to parse as JSON
+            structured_output = json.loads(str(structured_result))
+
+        logger.info(f"[REFLECT {reflect_id}] Generated structured output with {len(structured_output)} fields")
+        return structured_output
+
+    except Exception as e:
+        logger.warning(f"[REFLECT {reflect_id}] Failed to generate structured output: {e}")
+        return None
+
+
+async def run_reflect_agent(
+    llm_config: "LLMProvider",
+    bank_id: str,
+    query: str,
+    bank_profile: dict[str, Any],
+    lookup_fn: Callable[[str | None], Awaitable[dict[str, Any]]],
+    recall_fn: Callable[[str, int], Awaitable[dict[str, Any]]],
+    expand_fn: Callable[[list[str], str], Awaitable[dict[str, Any]]],
+    learn_fn: Callable[[MentalModelInput], Awaitable[dict[str, Any]]] | None = None,
+    context: str | None = None,
+    max_iterations: int = DEFAULT_MAX_ITERATIONS,
+    max_tokens: int | None = None,
+    response_schema: dict | None = None,
+    output_mode: Literal["answer", "observations"] = "answer",
+) -> ReflectAgentResult:
+    """
+    Execute the reflect agent loop using native tool calling.
+
+    The agent iteratively calls tools to gather information and learn,
+    then provides a final answer via the done() tool.
+
+    Args:
+        llm_config: LLM provider for agent calls
+        bank_id: Bank identifier
+        query: Question to answer
+        bank_profile: Bank profile with name and mission
+        lookup_fn: Tool callback for lookup (model_id) -> result
+        recall_fn: Tool callback for recall (query, max_tokens) -> result
+        expand_fn: Tool callback for expand (memory_id, depth) -> result
+        learn_fn: Optional tool callback for learn (MentalModelInput) -> result.
+                  If None, learn tool is disabled.
+        context: Optional additional context
+        max_iterations: Maximum number of iterations before forcing response
+        max_tokens: Maximum tokens for the final response
+        response_schema: Optional JSON Schema for structured output in final response
+        output_mode: "answer" returns final text, "observations" returns structured observations
+
+    Returns:
+        ReflectAgentResult with final answer and metadata
+    """
+    enable_learn = learn_fn is not None
+    reflect_id = f"{bank_id[:8]}-{int(time.time() * 1000) % 100000}"
+    start_time = time.time()
+
+    # Get tools for this agent
+    tools = get_reflect_tools(enable_learn=enable_learn, output_mode=output_mode)
+
+    # Build initial messages
+    system_prompt = build_system_prompt_for_tools(bank_profile, context, output_mode=output_mode)
+    messages: list[dict[str, Any]] = [
+        {"role": "system", "content": system_prompt},
+        {"role": "user", "content": query},
+    ]
+
+    # Tracking
+    mental_models_created: list[str] = []
+    total_tools_called = 0
+    tool_trace: list[ToolCall] = []
+    tool_trace_summary: list[dict[str, Any]] = []
+    llm_trace: list[dict[str, Any]] = []
+    context_history: list[dict[str, Any]] = []  # For final prompt fallback
+
+    # Track available IDs for validation (prevents hallucinated citations)
+    available_memory_ids: set[str] = set()
+    available_model_ids: set[str] = set()
+
+    # In answer mode, pre-fetch mental models so the agent always starts with this knowledge
+    if output_mode == "answer":
+        prefetch_start = time.time()
+        models_result = await lookup_fn(None)  # List all mental models
+        prefetch_duration = int((time.time() - prefetch_start) * 1000)
+
+        # Track available model IDs
+        if isinstance(models_result, dict) and "models" in models_result:
+            for model in models_result["models"]:
+                if "id" in model:
+                    available_model_ids.add(model["id"])
+
+        # Add to context history for the agent
+        context_history.append({"tool": "list_mental_models", "output": models_result})
+
+        # Add to tool trace
+        tool_trace.append(
+            ToolCall(
+                tool="list_mental_models",
+                input={"tool": "list_mental_models"},
+                output=models_result,
+                duration_ms=prefetch_duration,
+                iteration=0,
+            )
+        )
+        tool_trace_summary.append(
+            {
+                "tool": "list_mental_models",
+                "input_summary": "(prefetch)",
+                "duration_ms": prefetch_duration,
+                "output_chars": len(json.dumps(models_result, default=str)),
+            }
+        )
+        total_tools_called += 1
+
+        # Include in the user message so the agent sees it
+        models_info = json.dumps(models_result, indent=2, default=str)
+        messages[1]["content"] = f"{query}\n\n## Available Mental Models (pre-fetched)\n```json\n{models_info}\n```"
+
+    def _get_llm_trace() -> list[LLMCall]:
+        return [LLMCall(scope=c["scope"], duration_ms=c["duration_ms"]) for c in llm_trace]
+
+    def _log_completion(answer: str, iterations: int, forced: bool = False):
+        elapsed_ms = int((time.time() - start_time) * 1000)
+        tools_summary = (
+            ", ".join(
+                f"{t['tool']}({t['input_summary']})={t['duration_ms']}ms/{t.get('output_chars', 0)}c"
+                for t in tool_trace_summary
+            )
+            or "none"
+        )
+        llm_summary = ", ".join(f"{c['scope']}={c['duration_ms']}ms" for c in llm_trace) or "none"
+        total_llm_ms = sum(c["duration_ms"] for c in llm_trace)
+        total_tools_ms = sum(t["duration_ms"] for t in tool_trace_summary)
+
+        answer_preview = answer[:100] + "..." if len(answer) > 100 else answer
+        mode = "forced" if forced else "done"
+        logger.info(
+            f"[REFLECT {reflect_id}] {mode} | "
+            f"query='{query[:50]}...' | "
+            f"iterations={iterations} | "
+            f"llm=[{llm_summary}] ({total_llm_ms}ms) | "
+            f"tools=[{tools_summary}] ({total_tools_ms}ms) | "
+            f"answer='{answer_preview}' | "
+            f"total={elapsed_ms}ms"
+        )
+
+    for iteration in range(max_iterations):
+        is_last = iteration == max_iterations - 1
+
+        if is_last:
+            # Force text response on last iteration - no tools
+            prompt = build_final_prompt(query, context_history, bank_profile, context)
+            llm_start = time.time()
+            response = await llm_config.call(
+                messages=[
+                    {"role": "system", "content": FINAL_SYSTEM_PROMPT},
+                    {"role": "user", "content": prompt},
+                ],
+                scope="reflect_agent_final",
+                max_completion_tokens=max_tokens,
+            )
+            llm_trace.append({"scope": "final", "duration_ms": int((time.time() - llm_start) * 1000)})
+            answer = response.strip()
+
+            # Generate structured output if schema provided
+            structured_output = None
+            if response_schema and answer:
+                structured_output = await _generate_structured_output(answer, response_schema, llm_config, reflect_id)
+
+            _log_completion(answer, iteration + 1, forced=True)
+            return ReflectAgentResult(
+                text=answer,
+                structured_output=structured_output,
+                iterations=iteration + 1,
+                tools_called=total_tools_called,
+                mental_models_created=mental_models_created,
+                tool_trace=tool_trace,
+                llm_trace=_get_llm_trace(),
+            )
+
+        # Call LLM with tools
+        llm_start = time.time()
+
+        try:
+            result = await llm_config.call_with_tools(
+                messages=messages,
+                tools=tools,
+                scope="reflect_agent",
+                tool_choice="required" if iteration == 0 else "auto",  # Force tool use on first iteration
+            )
+            llm_duration = int((time.time() - llm_start) * 1000)
+            llm_trace.append({"scope": f"agent_{iteration + 1}", "duration_ms": llm_duration})
+
+        except Exception:
+            llm_trace.append(
+                {"scope": f"agent_{iteration + 1}_err", "duration_ms": int((time.time() - llm_start) * 1000)}
+            )
+            # Guardrail: If no evidence gathered yet, retry
+            has_gathered_evidence = bool(available_memory_ids) or bool(available_model_ids)
+            if not has_gathered_evidence and iteration < max_iterations - 1:
+                continue
+            prompt = build_final_prompt(query, context_history, bank_profile, context)
+            llm_start = time.time()
+            response = await llm_config.call(
+                messages=[
+                    {"role": "system", "content": FINAL_SYSTEM_PROMPT},
+                    {"role": "user", "content": prompt},
+                ],
+                scope="reflect_agent_final",
+                max_completion_tokens=max_tokens,
+            )
+            llm_trace.append({"scope": "final", "duration_ms": int((time.time() - llm_start) * 1000)})
+            answer = response.strip()
+
+            # Generate structured output if schema provided
+            structured_output = None
+            if response_schema and answer:
+                structured_output = await _generate_structured_output(answer, response_schema, llm_config, reflect_id)
+
+            _log_completion(answer, iteration + 1, forced=True)
+            return ReflectAgentResult(
+                text=answer,
+                structured_output=structured_output,
+                iterations=iteration + 1,
+                tools_called=total_tools_called,
+                mental_models_created=mental_models_created,
+                tool_trace=tool_trace,
+                llm_trace=_get_llm_trace(),
+            )
+
+        # No tool calls - LLM wants to respond with text
+        if not result.tool_calls:
+            if result.content:
+                answer = result.content.strip()
+
+                # Generate structured output if schema provided
+                structured_output = None
+                if response_schema and answer:
+                    structured_output = await _generate_structured_output(
+                        answer, response_schema, llm_config, reflect_id
+                    )
+
+                _log_completion(answer, iteration + 1)
+                return ReflectAgentResult(
+                    text=answer,
+                    structured_output=structured_output,
+                    iterations=iteration + 1,
+                    tools_called=total_tools_called,
+                    mental_models_created=mental_models_created,
+                    tool_trace=tool_trace,
+                    llm_trace=_get_llm_trace(),
+                )
+            # Empty response, force final
+            prompt = build_final_prompt(query, context_history, bank_profile, context)
+            llm_start = time.time()
+            response = await llm_config.call(
+                messages=[
+                    {"role": "system", "content": FINAL_SYSTEM_PROMPT},
+                    {"role": "user", "content": prompt},
+                ],
+                scope="reflect_agent_final",
+                max_completion_tokens=max_tokens,
+            )
+            llm_trace.append({"scope": "final", "duration_ms": int((time.time() - llm_start) * 1000)})
+            answer = response.strip()
+
+            # Generate structured output if schema provided
+            structured_output = None
+            if response_schema and answer:
+                structured_output = await _generate_structured_output(answer, response_schema, llm_config, reflect_id)
+
+            _log_completion(answer, iteration + 1, forced=True)
+            return ReflectAgentResult(
+                text=answer,
+                structured_output=structured_output,
+                iterations=iteration + 1,
+                tools_called=total_tools_called,
+                mental_models_created=mental_models_created,
+                tool_trace=tool_trace,
+                llm_trace=_get_llm_trace(),
+            )
+
+        # Check for done tool call
+        done_call = next((tc for tc in result.tool_calls if tc.name == "done"), None)
+        if done_call:
+            # Guardrail: Require evidence before done
+            has_gathered_evidence = bool(available_memory_ids) or bool(available_model_ids)
+            if not has_gathered_evidence and iteration < max_iterations - 1:
+                # Add assistant message and fake tool result asking for evidence
+                messages.append(
+                    {
+                        "role": "assistant",
+                        "tool_calls": [_tool_call_to_dict(done_call)],
+                    }
+                )
+                messages.append(
+                    {
+                        "role": "tool",
+                        "tool_call_id": done_call.id,
+                        "content": json.dumps(
+                            {
+                                "error": "You must call recall() or list_mental_models() to gather evidence before providing your final answer."
+                            }
+                        ),
+                    }
+                )
+                continue
+
+            # Process done tool
+            return await _process_done_tool(
+                done_call,
+                output_mode,
+                available_memory_ids,
+                available_model_ids,
+                iteration + 1,
+                total_tools_called,
+                mental_models_created,
+                tool_trace,
+                _get_llm_trace(),
+                _log_completion,
+                reflect_id,
+                llm_config=llm_config,
+                response_schema=response_schema,
+            )
+
+        # Execute other tools in parallel
+        other_tools = [tc for tc in result.tool_calls if tc.name != "done"]
+        if other_tools:
+            # Add assistant message with tool calls
+            messages.append(
+                {
+                    "role": "assistant",
+                    "tool_calls": [_tool_call_to_dict(tc) for tc in other_tools],
+                }
+            )
+
+            # Execute tools in parallel
+            tool_tasks = [
+                _execute_tool_with_timing(tc, lookup_fn, recall_fn, expand_fn, learn_fn) for tc in other_tools
+            ]
+            tool_results = await asyncio.gather(*tool_tasks, return_exceptions=True)
+            total_tools_called += len(other_tools)
+
+            # Process results and add to messages
+            for tc, result_data in zip(other_tools, tool_results):
+                if isinstance(result_data, Exception):
+                    # Tool execution failed - log and raise to fail the request
+                    logger.error(f"[REFLECT {reflect_id}] Tool {tc.name} failed with exception: {result_data}")
+                    raise RuntimeError(f"Reflect tool '{tc.name}' failed: {result_data}")
+
+                output, duration_ms = result_data
+
+                # Check if tool returned an error response
+                if isinstance(output, dict) and "error" in output:
+                    logger.error(f"[REFLECT {reflect_id}] Tool {tc.name} returned error: {output['error']}")
+                    raise RuntimeError(f"Reflect tool '{tc.name}' error: {output['error']}")
+
+                # Track created mental models
+                if tc.name == "learn" and isinstance(output, dict) and "model_id" in output:
+                    mental_models_created.append(output["model_id"])
+
+                # Track available memory IDs from recall
+                if tc.name == "recall" and isinstance(output, dict) and "memories" in output:
+                    for memory in output["memories"]:
+                        if "id" in memory:
+                            available_memory_ids.add(memory["id"])
+
+                # Track available model IDs
+                if tc.name in ("list_mental_models", "get_mental_model") and isinstance(output, dict):
+                    if output.get("found") and "model" in output:
+                        model_id = output["model"].get("id")
+                        if model_id:
+                            available_model_ids.add(model_id)
+                    elif "models" in output:
+                        for model in output["models"]:
+                            if "id" in model:
+                                available_model_ids.add(model["id"])
+
+                # Add tool result message
+                messages.append(
+                    {
+                        "role": "tool",
+                        "tool_call_id": tc.id,
+                        "content": json.dumps(output, default=str),
+                    }
+                )
+
+                # Track for logging and context history
+                input_dict = {"tool": tc.name, **tc.arguments}
+                input_summary = _summarize_input(tc.name, tc.arguments)
+
+                tool_trace.append(
+                    ToolCall(
+                        tool=tc.name, input=input_dict, output=output, duration_ms=duration_ms, iteration=iteration + 1
+                    )
+                )
+
+                try:
+                    output_chars = len(json.dumps(output))
+                except (TypeError, ValueError):
+                    output_chars = len(str(output))
+
+                tool_trace_summary.append(
+                    {
+                        "tool": tc.name,
+                        "input_summary": input_summary,
+                        "duration_ms": duration_ms,
+                        "output_chars": output_chars,
+                    }
+                )
+
+                # Keep context history for fallback final prompt
+                context_history.append({"tool": tc.name, "input": input_dict, "output": output})
+
+    # Should not reach here
+    answer = "I was unable to formulate a complete answer within the iteration limit."
+    _log_completion(answer, max_iterations, forced=True)
+    return ReflectAgentResult(
+        text=answer,
+        iterations=max_iterations,
+        tools_called=total_tools_called,
+        mental_models_created=mental_models_created,
+        tool_trace=tool_trace,
+        llm_trace=_get_llm_trace(),
+    )
+
+
+def _tool_call_to_dict(tc: "LLMToolCall") -> dict[str, Any]:
+    """Convert LLMToolCall to OpenAI message format."""
+    return {
+        "id": tc.id,
+        "type": "function",
+        "function": {
+            "name": tc.name,
+            "arguments": json.dumps(tc.arguments),
+        },
+    }
+
+
+async def _process_done_tool(
+    done_call: "LLMToolCall",
+    output_mode: str,
+    available_memory_ids: set[str],
+    available_model_ids: set[str],
+    iterations: int,
+    total_tools_called: int,
+    mental_models_created: list[str],
+    tool_trace: list[ToolCall],
+    llm_trace: list[LLMCall],
+    log_completion: Callable,
+    reflect_id: str,
+    llm_config: "LLMProvider | None" = None,
+    response_schema: dict | None = None,
+) -> ReflectAgentResult:
+    """Process the done tool call and return the result."""
+    args = done_call.arguments
+
+    if output_mode == "observations" and "observations" in args:
+        # Process observations - handle both list and nested {"observations": [...]} format
+        observations: list[Observation] = []
+        used_memory_ids: list[str] = []
+
+        obs_list = args["observations"]
+        # Handle nested format where LLM outputs {"observations": [...]} instead of just [...]
+        if isinstance(obs_list, dict) and "observations" in obs_list:
+            obs_list = obs_list["observations"]
+
+        for obs_data in obs_list:
+            validated_mids = []
+            for mid in obs_data.get("memory_ids", []):
+                if mid in available_memory_ids:
+                    validated_mids.append(mid)
+                    if mid not in used_memory_ids:
+                        used_memory_ids.append(mid)
+
+            observations.append(
+                Observation(
+                    title=obs_data.get("title", ""),
+                    text=obs_data.get("text", ""),
+                    memory_ids=validated_mids,
+                )
+            )
+
+        # Build text from observations
+        text_parts = []
+        for obs in observations:
+            if obs.title:
+                text_parts.append(f"## {obs.title}\n{obs.text}")
+            else:
+                text_parts.append(obs.text)
+        answer = "\n\n".join(text_parts)
+
+        log_completion(answer, iterations)
+        return ReflectAgentResult(
+            text=answer,
+            observations=observations,
+            iterations=iterations,
+            tools_called=total_tools_called,
+            mental_models_created=mental_models_created,
+            tool_trace=tool_trace,
+            llm_trace=llm_trace,
+            used_memory_ids=used_memory_ids,
+        )
+
+    # Default: answer mode
+    answer = args.get("answer", "").strip()
+    if not answer:
+        answer = "No answer provided."
+
+    # Validate IDs
+    used_memory_ids = [mid for mid in args.get("memory_ids", []) if mid in available_memory_ids]
+    used_model_ids = [mid for mid in args.get("model_ids", []) if mid in available_model_ids]
+
+    # Generate structured output if schema provided
+    structured_output = None
+    if response_schema and llm_config and answer:
+        structured_output = await _generate_structured_output(answer, response_schema, llm_config, reflect_id)
+
+    log_completion(answer, iterations)
+    return ReflectAgentResult(
+        text=answer,
+        structured_output=structured_output,
+        iterations=iterations,
+        tools_called=total_tools_called,
+        mental_models_created=mental_models_created,
+        tool_trace=tool_trace,
+        llm_trace=llm_trace,
+        used_memory_ids=used_memory_ids,
+        used_model_ids=used_model_ids,
+    )
+
+
+async def _execute_tool_with_timing(
+    tc: "LLMToolCall",
+    lookup_fn: Callable[[str | None], Awaitable[dict[str, Any]]],
+    recall_fn: Callable[[str, int], Awaitable[dict[str, Any]]],
+    expand_fn: Callable[[list[str], str], Awaitable[dict[str, Any]]],
+    learn_fn: Callable[[MentalModelInput], Awaitable[dict[str, Any]]] | None = None,
+) -> tuple[dict[str, Any], int]:
+    """Execute a tool call and return result with timing."""
+    start = time.time()
+    result = await _execute_tool(tc.name, tc.arguments, lookup_fn, recall_fn, expand_fn, learn_fn)
+    duration_ms = int((time.time() - start) * 1000)
+    return result, duration_ms
+
+
+async def _execute_tool(
+    tool_name: str,
+    args: dict[str, Any],
+    lookup_fn: Callable[[str | None], Awaitable[dict[str, Any]]],
+    recall_fn: Callable[[str, int], Awaitable[dict[str, Any]]],
+    expand_fn: Callable[[list[str], str], Awaitable[dict[str, Any]]],
+    learn_fn: Callable[[MentalModelInput], Awaitable[dict[str, Any]]] | None = None,
+) -> dict[str, Any]:
+    """Execute a single tool by name."""
+    if tool_name == "list_mental_models":
+        return await lookup_fn(None)
+
+    elif tool_name == "get_mental_model":
+        model_id = args.get("model_id")
+        if not model_id:
+            return {"error": "get_mental_model requires model_id"}
+        return await lookup_fn(model_id)
+
+    elif tool_name == "recall":
+        query = args.get("query")
+        if not query:
+            return {"error": "recall requires a query parameter"}
+        max_tokens = max(args.get("max_tokens") or 2048, 1000)  # Default 2048, min 1000
+        return await recall_fn(query, max_tokens)
+
+    elif tool_name == "learn":
+        if learn_fn is None:
+            return {"error": "learn tool is not available"}
+        name = args.get("name")
+        description = args.get("description")
+        if not name or not description:
+            return {"error": "learn requires name and description"}
+        return await learn_fn(MentalModelInput(name=name, description=description))
+
+    elif tool_name == "expand":
+        memory_ids = args.get("memory_ids", [])
+        if not memory_ids:
+            return {"error": "expand requires memory_ids"}
+        depth = args.get("depth", "chunk")
+        return await expand_fn(memory_ids, depth)
+
+    else:
+        return {"error": f"Unknown tool: {tool_name}"}
+
+
+def _summarize_input(tool_name: str, args: dict[str, Any]) -> str:
+    """Create a summary of tool input for logging, showing all params."""
+    if tool_name == "list_mental_models":
+        return "()"
+    elif tool_name == "get_mental_model":
+        return f"(model_id={args.get('model_id', '?')})"
+    elif tool_name == "recall":
+        query = args.get("query", "")
+        query_preview = f"'{query[:30]}...'" if len(query) > 30 else f"'{query}'"
+        # Show actual value used (default 2048, min 1000)
+        max_tokens = max(args.get("max_tokens") or 2048, 1000)
+        return f"(query={query_preview}, max_tokens={max_tokens})"
+    elif tool_name == "learn":
+        name = args.get("name", "?")
+        desc = args.get("description", "")
+        desc_preview = f"'{desc[:20]}...'" if len(desc) > 20 else f"'{desc}'"
+        return f"(name='{name}', description={desc_preview})"
+    elif tool_name == "expand":
+        memory_ids = args.get("memory_ids", [])
+        depth = args.get("depth", "chunk")
+        return f"(memory_ids=[{len(memory_ids)} ids], depth={depth})"
+    elif tool_name == "done":
+        answer = args.get("answer", "")
+        answer_preview = f"'{answer[:30]}...'" if len(answer) > 30 else f"'{answer}'"
+        memory_ids = args.get("memory_ids", [])
+        model_ids = args.get("model_ids", [])
+        return f"(answer={answer_preview}, memory_ids={len(memory_ids)}, model_ids={len(model_ids)})"
+    return str(args)

hindsight-api/hindsight_api/engine/reflect/models.py

@@ -0,0 +1,114 @@
+"""
+Pydantic models for the reflect agent.
+"""
+
+from typing import Any, Literal
+
+from pydantic import BaseModel, Field
+
+
+class MentalModelObservation(BaseModel):
+    """An observation within a mental model with its supporting memories."""
+
+    title: str = Field(description="Observation header (can be empty for intro)")
+    text: str = Field(description="Observation content - no headers, use lists/tables/bold")
+    memory_ids: list[str] = Field(default_factory=list, description="Memory IDs supporting this observation")
+
+
+class MentalModelInput(BaseModel):
+    """Input for the learn tool to create a mental model placeholder.
+
+    The agent only specifies name and description - the actual content/observations
+    are generated during refresh, similar to pinned models.
+    """
+
+    name: str = Field(description="Human-readable name for the mental model")
+    description: str = Field(description="What to track - used as prompt for content generation during refresh")
+    entity_id: str | None = Field(default=None, description="Optional link to existing entity ID")
+
+
+class AnswerSection(BaseModel):
+    """A section of the answer with its supporting evidence (DEPRECATED)."""
+
+    title: str = Field(description="Section header/title")
+    text: str = Field(description="Section content")
+    memory_ids: list[str] = Field(default_factory=list, description="Memory IDs supporting this section")
+    model_ids: list[str] = Field(default_factory=list, description="Mental model IDs supporting this section")
+
+
+class ReflectAction(BaseModel):
+    """Single action the reflect agent can take."""
+
+    tool: Literal["list_mental_models", "get_mental_model", "recall", "learn", "expand", "done"] = Field(
+        description="Tool to invoke: list_mental_models, get_mental_model, recall, learn, expand, or done"
+    )
+    # Tool-specific parameters
+    model_id: str | None = Field(default=None, description="Mental model ID for get_mental_model")
+    query: str | None = Field(default=None, description="Search query for recall")
+    max_tokens: int | None = Field(default=None, description="Max tokens for recall results (default 2048)")
+    mental_model: MentalModelInput | None = Field(default=None, description="Mental model to create/update for learn")
+    memory_ids: list[str] | None = Field(default=None, description="Memory unit IDs for expand (batched)")
+    depth: Literal["chunk", "document"] | None = Field(default=None, description="Expansion depth for expand")
+    sections: list[AnswerSection] | None = Field(default=None, description="DEPRECATED: Use answer field instead")
+    observations: list[MentalModelObservation] | None = Field(
+        default=None, description="Observations for done action (when output_mode=observations)"
+    )
+    # Plain text answer fields (for output_mode=answer)
+    answer: str | None = Field(default=None, description="Plain text answer for done action (no markdown)")
+    answer_memory_ids: list[str] | None = Field(
+        default=None, description="Memory IDs supporting the answer", alias="memory_ids"
+    )
+    answer_model_ids: list[str] | None = Field(
+        default=None, description="Mental model IDs supporting the answer", alias="model_ids"
+    )
+    reasoning: str | None = Field(default=None, description="Brief reasoning for this action")
+
+
+class ReflectActionBatch(BaseModel):
+    """Batch of actions for parallel execution."""
+
+    actions: list[ReflectAction] = Field(description="List of actions to execute in parallel")
+
+
+class ToolCall(BaseModel):
+    """A single tool call made during reflect."""
+
+    tool: str = Field(description="Tool name: lookup, recall, learn, expand")
+    input: dict = Field(description="Tool input parameters")
+    output: dict = Field(description="Tool output/result")
+    duration_ms: int = Field(description="Execution time in milliseconds")
+    iteration: int = Field(default=0, description="Iteration number (1-based) when this tool was called")
+
+
+class LLMCall(BaseModel):
+    """A single LLM call made during reflect."""
+
+    scope: str = Field(description="Call scope: agent_1, agent_2, final, etc.")
+    duration_ms: int = Field(description="Execution time in milliseconds")
+
+
+class Observation(BaseModel):
+    """A single observation with supporting memories."""
+
+    title: str = Field(description="Observation title/header")
+    text: str = Field(description="Observation content")
+    memory_ids: list[str] = Field(default_factory=list, description="Memory IDs supporting this observation")
+
+
+class ReflectAgentResult(BaseModel):
+    """Result from the reflect agent."""
+
+    text: str = Field(description="Final answer text")
+    observations: list[Observation] = Field(
+        default_factory=list, description="Structured observations (when output_mode=observations)"
+    )
+    structured_output: dict[str, Any] | None = Field(
+        default=None, description="Structured output parsed according to provided response_schema"
+    )
+    iterations: int = Field(default=0, description="Number of iterations taken")
+    tools_called: int = Field(default=0, description="Total number of tool calls made")
+    mental_models_created: list[str] = Field(default_factory=list, description="IDs of mental models created/updated")
+    tool_trace: list[ToolCall] = Field(default_factory=list, description="Trace of all tool calls made")
+    llm_trace: list[LLMCall] = Field(default_factory=list, description="Trace of all LLM calls made")
+    used_memory_ids: list[str] = Field(default_factory=list, description="Validated memory IDs actually used in answer")
+    used_model_ids: list[str] = Field(default_factory=list, description="Validated model IDs actually used in answer")

hindsight-api/hindsight_api/engine/reflect/prompts.py

@@ -0,0 +1,312 @@
+"""
+System prompts for the reflect agent.
+"""
+
+import json
+from typing import Any
+
+
+def build_system_prompt_for_tools(
+    bank_profile: dict[str, Any],
+    context: str | None = None,
+    output_mode: str = "answer",
+) -> str:
+    """
+    Build the system prompt for tool-calling reflect agent.
+
+    This is a simplified prompt since tools are defined separately via the tools parameter.
+
+    Args:
+        bank_profile: Bank profile with name and mission
+        context: Optional additional context
+        output_mode: "answer" for plain text response, "observations" for structured observations
+    """
+    name = bank_profile.get("name", "Assistant")
+    mission = bank_profile.get("mission", "")
+
+    # Build critical rules based on mode
+    if output_mode == "observations":
+        no_info_rule = "- Only say 'I don't have information' AFTER trying recall with no relevant results"
+    else:
+        no_info_rule = (
+            "- Only say 'I don't have information' AFTER trying list_mental_models AND recall with no relevant results"
+        )
+
+    parts = [
+        "You are a reflection agent that answers questions by reasoning over retrieved memories.",
+        "",
+        "## CRITICAL RULES",
+        "- You must NEVER fabricate information that has no basis in retrieved data",
+        "- You SHOULD synthesize, infer, and reason from the retrieved memories",
+        "- You MUST call recall() before saying you don't have information",
+        no_info_rule,
+        "",
+        "## How to Reason",
+        "- If memories mention someone did an activity, you can infer they likely enjoyed it",
+        "- Synthesize a coherent narrative from related memories",
+        "- Be a thoughtful interpreter, not just a literal repeater",
+        "- When the exact answer isn't stated, use what IS stated to give the best answer",
+        "",
+        "## Query Strategy (IMPORTANT)",
+        "recall() uses semantic search. NEVER just echo the user's question - decompose it into targeted searches:",
+        "",
+        "BAD: User asks 'recurring lesson themes between students' → recall('recurring lesson themes between students')",
+        "GOOD: Break it down into component searches:",
+        "  1. recall('lessons') - find all lesson-related memories",
+        "  2. recall('teaching sessions') - alternative phrasing",
+        "  3. recall('student progress') - find student-related memories",
+        "  4. recall('topics taught') - find subject matter",
+        "",
+        "Think: What ENTITIES and CONCEPTS does this question involve? Search for each separately.",
+        "- Questions about patterns → search for the individual instances first",
+        "- Questions comparing things → search for each thing separately",
+        "- Questions about relationships → search for each party involved",
+        "",
+        "## Workflow",
+    ]
+
+    # Mode-specific workflow and output format
+    if output_mode == "observations":
+        # Observations mode: for mental model generation - no mental model lookup tools
+        parts.extend(
+            [
+                "1. DECOMPOSE the topic into component searches (see Query Strategy above)",
+                "   - Don't search for the topic name itself - search for related concepts",
+                "   - Example for 'Coffee preferences': search 'coffee', 'drinks', 'morning routine', 'caffeine'",
+                "2. Run multiple recall() calls with varied, targeted queries",
+                "3. IMPORTANT: Use expand(memory_ids, 'chunk') to verify memories before using them",
+                "   - Always verify the source chunk to confirm the memory is actually relevant",
+                "   - Don't assume a memory is relevant based on the summary alone",
+                "   - Only include memories you've verified via expand()",
+                "4. When ready, call done() with MULTIPLE structured observations",
+                "",
+                "## Output Format: MULTIPLE Structured Observations",
+                "",
+                "CRITICAL: You MUST create MULTIPLE separate observations in the array - one for each theme.",
+                "Do NOT put all content in a single observation!",
+                "",
+                "- Create 3-8 separate observations, each as its OWN item in the observations array",
+                "- Each observation covers ONE specific theme (preferences, history, relationships, etc.)",
+                "- Each observation has: title (short header), text (content), memory_ids (full UUIDs)",
+                "",
+                "Text format for each observation:",
+                "- Main insight or finding (no markdown headers)",
+                "- End with 'Key evidence:' section containing DIRECT QUOTES from memories in *italics*",
+                "- Quote the actual memory text, don't summarize - use *italics* for citations",
+                "",
+                "Example done() call with MULTIPLE observations:",
+                "```json",
+                "{",
+                '  "observations": [',
+                "    {",
+                '      "title": "Work Preferences",',
+                '      "text": "Prefers async communication and flexible schedules.\\n\\nKey evidence:\\n- *I prefer Slack over calls for most communication*\\n- *Flexible hours help me do my best work*",',
+                '      "memory_ids": ["abc123-full-uuid", "def456-full-uuid"]',
+                "    },",
+                "    {",
+                '      "title": "Technical Background",',
+                '      "text": "Has extensive ML experience spanning a decade.\\n\\nKey evidence:\\n- *I have 10 years of experience in machine learning*\\n- *Led the ML team at my previous company*",',
+                '      "memory_ids": ["ghi789-full-uuid"]',
+                "    }",
+                "  ]",
+                "}",
+                "```",
+            ]
+        )
+    else:
+        # Answer mode: include mental model lookup in workflow
+        parts.extend(
+            [
+                "1. Review the pre-fetched mental models for relevant synthesized knowledge",
+                "2. If relevant, call get_mental_model(model_id) for full observations",
+                "3. DECOMPOSE the question into component searches (see Query Strategy above)",
+                "   - Identify entities and concepts in the question",
+                "   - Search for each separately with targeted queries",
+                "4. Run multiple recall() calls - don't just echo the user's question",
+                "5. Use expand() if you need more context on specific memories",
+                "6. If you discover an important recurring topic worth tracking, use learn() to create a mental model",
+                "7. When ready, call done() with your answer and supporting memory_ids",
+                "",
+                "## When to Use learn()",
+                "Use learn() to create a new mental model when you discover:",
+                "- A person, project, or concept that appears frequently in memories",
+                "- An important topic the user seems to care about but has no mental model for",
+                "- A pattern or relationship worth synthesizing for future reference",
+                "Example: learn(name='Project Alpha', description='Track goals, status, and key decisions for Project Alpha')",
+                "",
+                "## Output Format: Plain Text Answer",
+                "Call done() with a plain text 'answer' field.",
+                "- Do NOT use markdown formatting",
+                "- NEVER include memory IDs, UUIDs, or 'Memory references' in the answer text",
+                "- Put memory IDs ONLY in the memory_ids array parameter, not in the answer",
+            ]
+        )
+
+    parts.append("")
+    parts.append(f"## Memory Bank: {name}")
+
+    if mission:
+        parts.append(f"Mission: {mission}")
+
+    # Disposition traits
+    disposition = bank_profile.get("disposition", {})
+    if disposition:
+        traits = []
+        if "skepticism" in disposition:
+            traits.append(f"skepticism={disposition['skepticism']}")
+        if "literalism" in disposition:
+            traits.append(f"literalism={disposition['literalism']}")
+        if "empathy" in disposition:
+            traits.append(f"empathy={disposition['empathy']}")
+        if traits:
+            parts.append(f"Disposition: {', '.join(traits)}")
+
+    if context:
+        parts.append(f"\n## Additional Context\n{context}")
+
+    return "\n".join(parts)
+
+
+def build_agent_prompt(
+    query: str,
+    context_history: list[dict],
+    bank_profile: dict,
+    additional_context: str | None = None,
+) -> str:
+    """Build the user prompt for the reflect agent."""
+    parts = []
+
+    # Bank identity
+    name = bank_profile.get("name", "Assistant")
+    mission = bank_profile.get("mission", "")
+
+    parts.append(f"## Memory Bank Context\nName: {name}")
+    if mission:
+        parts.append(f"Mission: {mission}")
+
+    # Disposition traits if present
+    disposition = bank_profile.get("disposition", {})
+    if disposition:
+        traits = []
+        if "skepticism" in disposition:
+            traits.append(f"skepticism={disposition['skepticism']}")
+        if "literalism" in disposition:
+            traits.append(f"literalism={disposition['literalism']}")
+        if "empathy" in disposition:
+            traits.append(f"empathy={disposition['empathy']}")
+        if traits:
+            parts.append(f"Disposition: {', '.join(traits)}")
+
+    # Additional context from caller
+    if additional_context:
+        parts.append(f"\n## Additional Context\n{additional_context}")
+
+    # Tool call history
+    if context_history:
+        parts.append("\n## Tool Results (synthesize and reason from this data)")
+        for i, entry in enumerate(context_history, 1):
+            tool = entry["tool"]
+            output = entry["output"]
+            # Format as proper JSON for LLM readability
+            try:
+                output_str = json.dumps(output, indent=2, default=str)
+            except (TypeError, ValueError):
+                output_str = str(output)
+            parts.append(f"\n### Call {i}: {tool}\n```json\n{output_str}\n```")
+
+    # The question
+    parts.append(f"\n## Question\n{query}")
+
+    # Instructions
+    if context_history:
+        parts.append(
+            "\n## Instructions\n"
+            "Based on the tool results above, either call more tools or provide your final answer. "
+            "Synthesize and reason from the data - make reasonable inferences when helpful. "
+            "If you have related information, use it to give the best possible answer."
+        )
+    else:
+        parts.append(
+            "\n## Instructions\n"
+            "Start by calling list_mental_models() to see available mental models - they contain pre-synthesized knowledge. "
+            "If a relevant model exists, use get_mental_model(model_id) to get its observations. "
+            "Then use recall(query) for specific details not covered by mental models."
+        )
+
+    return "\n".join(parts)
+
+
+def build_final_prompt(
+    query: str,
+    context_history: list[dict],
+    bank_profile: dict,
+    additional_context: str | None = None,
+) -> str:
+    """Build the final prompt when forcing a text response (no tools)."""
+    parts = []
+
+    # Bank identity
+    name = bank_profile.get("name", "Assistant")
+    mission = bank_profile.get("mission", "")
+
+    parts.append(f"## Memory Bank Context\nName: {name}")
+    if mission:
+        parts.append(f"Mission: {mission}")
+
+    # Disposition traits if present
+    disposition = bank_profile.get("disposition", {})
+    if disposition:
+        traits = []
+        if "skepticism" in disposition:
+            traits.append(f"skepticism={disposition['skepticism']}")
+        if "literalism" in disposition:
+            traits.append(f"literalism={disposition['literalism']}")
+        if "empathy" in disposition:
+            traits.append(f"empathy={disposition['empathy']}")
+        if traits:
+            parts.append(f"Disposition: {', '.join(traits)}")
+
+    # Additional context from caller
+    if additional_context:
+        parts.append(f"\n## Additional Context\n{additional_context}")
+
+    # Tool call history
+    if context_history:
+        parts.append("\n## Retrieved Data (synthesize and reason from this data)")
+        for entry in context_history:
+            tool = entry["tool"]
+            output = entry["output"]
+            # Format as proper JSON for LLM readability
+            try:
+                output_str = json.dumps(output, indent=2, default=str)
+            except (TypeError, ValueError):
+                output_str = str(output)
+            parts.append(f"\n### From {tool}:\n```json\n{output_str}\n```")
+    else:
+        parts.append("\n## Retrieved Data\nNo data was retrieved.")
+
+    # The question
+    parts.append(f"\n## Question\n{query}")
+
+    # Final instructions
+    parts.append(
+        "\n## Instructions\n"
+        "Provide a thoughtful answer by synthesizing and reasoning from the retrieved data above. "
+        "You can make reasonable inferences from the memories, but don't completely fabricate information."
+        "If the exact answer isn't stated, use what IS stated to give the best possible answer. "
+        "Only say 'I don't have information' if the retrieved data is truly unrelated to the question."
+    )
+
+    return "\n".join(parts)
+
+
+FINAL_SYSTEM_PROMPT = """You are a thoughtful assistant that synthesizes answers from retrieved memories.
+
+Your approach:
+- Reason over the retrieved memories to answer the question
+- Make reasonable inferences when the exact answer isn't explicitly stated
+- Connect related memories to form a complete picture
+- Be helpful - if you have related information, use it to give the best possible answer
+
+Only say "I don't have information" if the retrieved data is truly unrelated to the question.
+Do NOT fabricate information that has no basis in the retrieved data."""

hindsight-api/hindsight_api/engine/reflect/tools.py

@@ -0,0 +1,425 @@
+"""
+Tool implementations for the reflect agent.
+"""
+
+import logging
+import re
+import uuid
+from typing import TYPE_CHECKING, Any
+
+from .models import MentalModelInput
+
+if TYPE_CHECKING:
+    from asyncpg import Connection
+
+    from ...api.http import RequestContext
+    from ..memory_engine import MemoryEngine
+
+logger = logging.getLogger(__name__)
+
+
+def generate_model_id(name: str) -> str:
+    """Generate a stable ID from mental model name."""
+    # Normalize: lowercase, replace spaces/special chars with hyphens
+    normalized = re.sub(r"[^a-z0-9]+", "-", name.lower()).strip("-")
+    # Truncate to reasonable length
+    return normalized[:50]
+
+
+async def tool_lookup(
+    conn: "Connection",
+    bank_id: str,
+    model_id: str | None = None,
+    tags: list[str] | None = None,
+    tags_match: str = "any",
+) -> dict[str, Any]:
+    """
+    List or get mental models.
+
+    Args:
+        conn: Database connection
+        bank_id: Bank identifier
+        model_id: Optional specific model ID to get (if None, lists all)
+        tags: Optional tags to filter models (when listing)
+        tags_match: How to match tags - "any" (OR), "all" (AND)
+
+    Returns:
+        Dict with either a list of models or a single model's details
+    """
+    if model_id:
+        # Get specific mental model with full details including observations
+        row = await conn.fetchrow(
+            """
+            SELECT id, subtype, name, description, observations, entity_id, last_updated
+            FROM mental_models
+            WHERE id = $1 AND bank_id = $2
+            """,
+            model_id,
+            bank_id,
+        )
+        if row:
+            # Parse observations JSON
+            obs_data = row["observations"] or {"observations": []}
+            if isinstance(obs_data, str):
+                import json
+
+                obs_data = json.loads(obs_data)
+            observations_raw = obs_data.get("observations", []) if isinstance(obs_data, dict) else obs_data
+
+            # Normalize observation format: map memory_ids/fact_ids to based_on
+            observations = []
+            for obs in observations_raw:
+                if isinstance(obs, dict):
+                    based_on = obs.get("memory_ids") or obs.get("fact_ids") or []
+                    observations.append(
+                        {
+                            "title": obs.get("title", ""),
+                            "text": obs.get("text", ""),
+                            "based_on": based_on,
+                        }
+                    )
+
+            return {
+                "found": True,
+                "model": {
+                    "id": row["id"],
+                    "subtype": row["subtype"],
+                    "name": row["name"],
+                    "description": row["description"],
+                    "observations": observations,  # [{title, text, based_on}, ...]
+                    "entity_id": str(row["entity_id"]) if row["entity_id"] else None,
+                    "last_updated": row["last_updated"].isoformat() if row["last_updated"] else None,
+                },
+            }
+        return {"found": False, "model_id": model_id}
+    else:
+        # List mental models (compact: id, name, description only)
+        # Full observations are retrieved via get_mental_model(model_id)
+        # Filter by tags if provided
+        if tags:
+            if tags_match == "all":
+                # All tags must match
+                rows = await conn.fetch(
+                    """
+                    SELECT id, subtype, name, description
+                    FROM mental_models
+                    WHERE bank_id = $1 AND tags @> $2::varchar[]
+                    ORDER BY last_updated DESC NULLS LAST, created_at DESC
+                    """,
+                    bank_id,
+                    tags,
+                )
+            else:
+                # Any tag matches (OR) - default
+                rows = await conn.fetch(
+                    """
+                    SELECT id, subtype, name, description
+                    FROM mental_models
+                    WHERE bank_id = $1 AND tags && $2::varchar[]
+                    ORDER BY last_updated DESC NULLS LAST, created_at DESC
+                    """,
+                    bank_id,
+                    tags,
+                )
+        else:
+            rows = await conn.fetch(
+                """
+                SELECT id, subtype, name, description
+                FROM mental_models
+                WHERE bank_id = $1
+                ORDER BY last_updated DESC NULLS LAST, created_at DESC
+                """,
+                bank_id,
+            )
+
+        return {
+            "count": len(rows),
+            "models": [
+                {
+                    "id": row["id"],
+                    "subtype": row["subtype"],
+                    "name": row["name"],
+                    "description": row["description"],
+                }
+                for row in rows
+            ],
+        }
+
+
+async def tool_recall(
+    memory_engine: "MemoryEngine",
+    bank_id: str,
+    query: str,
+    request_context: "RequestContext",
+    max_tokens: int = 2048,
+    max_results: int = 50,
+    tags: list[str] | None = None,
+    tags_match: str = "any",
+    connection_budget: int = 1,
+) -> dict[str, Any]:
+    """
+    Search memories using TEMPR retrieval.
+
+    Args:
+        memory_engine: Memory engine instance
+        bank_id: Bank identifier
+        query: Search query
+        request_context: Request context for authentication
+        max_tokens: Maximum tokens for results (default 2048)
+        max_results: Maximum number of results
+        tags: Filter by tags (includes untagged memories)
+        tags_match: How to match tags - "any" (OR), "all" (AND), or "exact"
+        connection_budget: Max DB connections for this recall (default 1 for internal ops)
+
+    Returns:
+        Dict with list of matching memories
+    """
+    result = await memory_engine.recall_async(
+        bank_id=bank_id,
+        query=query,
+        fact_type=["experience", "world"],  # Exclude opinions
+        max_tokens=max_tokens,
+        enable_trace=False,
+        request_context=request_context,
+        tags=tags,
+        tags_match=tags_match,
+        _connection_budget=connection_budget,
+    )
+
+    memories = []
+    for m in result.results[:max_results]:
+        memories.append(
+            {
+                "id": str(m.id),
+                "text": m.text,
+                "type": m.fact_type,
+                "entities": m.entities or [],
+                "occurred": m.occurred_start,  # Already ISO format string
+            }
+        )
+
+    return {
+        "query": query,
+        "count": len(memories),
+        "memories": memories,
+    }
+
+
+async def tool_learn(
+    conn: "Connection",
+    bank_id: str,
+    input: MentalModelInput,
+    tags: list[str] | None = None,
+) -> dict[str, Any]:
+    """
+    Create a mental model placeholder with subtype='learned'.
+
+    The agent only specifies name and description - actual observations are generated
+    in the background via refresh, similar to pinned models.
+
+    Args:
+        conn: Database connection
+        bank_id: Bank identifier
+        input: Mental model input data (name, description, optional entity_id)
+        tags: Tags to apply to new mental models (from reflect context)
+
+    Returns:
+        Dict with created model info including model_id for background generation
+    """
+    model_id = generate_model_id(input.name)
+
+    # Parse entity_id if provided
+    entity_uuid = None
+    if input.entity_id:
+        try:
+            entity_uuid = uuid.UUID(input.entity_id)
+        except ValueError:
+            logger.warning(f"Invalid entity_id format: {input.entity_id}")
+
+    # Check if model exists
+    existing = await conn.fetchrow(
+        "SELECT id FROM mental_models WHERE id = $1 AND bank_id = $2",
+        model_id,
+        bank_id,
+    )
+
+    if existing:
+        # Update description only - observations will be regenerated
+        await conn.execute(
+            """
+            UPDATE mental_models SET
+                description = $3,
+                entity_id = $4
+            WHERE id = $1 AND bank_id = $2
+            """,
+            model_id,
+            bank_id,
+            input.description,
+            entity_uuid,
+        )
+        status = "updated"
+    else:
+        # Insert new model placeholder - observations will be generated in background
+        await conn.execute(
+            """
+            INSERT INTO mental_models (id, bank_id, subtype, name, description, observations, entity_id, tags, created_at)
+            VALUES ($1, $2, 'learned', $3, $4, '{}'::jsonb, $5, $6, NOW())
+            """,
+            model_id,
+            bank_id,
+            input.name,
+            input.description,
+            entity_uuid,
+            tags or [],
+        )
+        status = "created"
+
+    logger.info(f"[REFLECT] Mental model '{model_id}' {status} in bank {bank_id} - pending background generation")
+
+    return {
+        "status": status,
+        "model_id": model_id,
+        "name": input.name,
+        "pending_generation": True,
+    }
+
+
+async def tool_expand(
+    conn: "Connection",
+    bank_id: str,
+    memory_ids: list[str],
+    depth: str,
+) -> dict[str, Any]:
+    """
+    Expand multiple memories to get chunk or document context.
+
+    Args:
+        conn: Database connection
+        bank_id: Bank identifier
+        memory_ids: List of memory unit IDs
+        depth: "chunk" or "document"
+
+    Returns:
+        Dict with results array, each containing memory, chunk, and optionally document data
+    """
+    if not memory_ids:
+        return {"error": "memory_ids is required and must not be empty"}
+
+    # Validate and convert UUIDs
+    valid_uuids: list[uuid.UUID] = []
+    errors: dict[str, str] = {}
+    for mid in memory_ids:
+        try:
+            valid_uuids.append(uuid.UUID(mid))
+        except ValueError:
+            errors[mid] = f"Invalid memory_id format: {mid}"
+
+    if not valid_uuids:
+        return {"error": "No valid memory IDs provided", "details": errors}
+
+    # Batch fetch all memory units
+    memories = await conn.fetch(
+        """
+        SELECT id, text, chunk_id, document_id, fact_type, context
+        FROM memory_units
+        WHERE id = ANY($1) AND bank_id = $2
+        """,
+        valid_uuids,
+        bank_id,
+    )
+    memory_map = {row["id"]: row for row in memories}
+
+    # Collect chunk_ids and document_ids for batch fetching
+    chunk_ids = [m["chunk_id"] for m in memories if m["chunk_id"]]
+    doc_ids_from_chunks: set[str] = set()
+    doc_ids_direct: set[str] = set()
+
+    # Batch fetch all chunks
+    chunk_map: dict[str, Any] = {}
+    if chunk_ids:
+        chunks = await conn.fetch(
+            """
+            SELECT chunk_id, chunk_text, chunk_index, document_id
+            FROM chunks
+            WHERE chunk_id = ANY($1)
+            """,
+            chunk_ids,
+        )
+        chunk_map = {row["chunk_id"]: row for row in chunks}
+        if depth == "document":
+            doc_ids_from_chunks = {c["document_id"] for c in chunks if c["document_id"]}
+
+    # Collect direct document IDs (memories without chunks)
+    if depth == "document":
+        for m in memories:
+            if not m["chunk_id"] and m["document_id"]:
+                doc_ids_direct.add(m["document_id"])
+
+    # Batch fetch all documents
+    doc_map: dict[str, Any] = {}
+    all_doc_ids = list(doc_ids_from_chunks | doc_ids_direct)
+    if all_doc_ids:
+        docs = await conn.fetch(
+            """
+            SELECT id, original_text, metadata, retain_params
+            FROM documents
+            WHERE id = ANY($1) AND bank_id = $2
+            """,
+            all_doc_ids,
+            bank_id,
+        )
+        doc_map = {row["id"]: row for row in docs}
+
+    # Build results
+    results: list[dict[str, Any]] = []
+    for mid, mem_uuid in zip(memory_ids, valid_uuids):
+        if mid in errors:
+            results.append({"memory_id": mid, "error": errors[mid]})
+            continue
+
+        memory = memory_map.get(mem_uuid)
+        if not memory:
+            results.append({"memory_id": mid, "error": f"Memory not found: {mid}"})
+            continue
+
+        item: dict[str, Any] = {
+            "memory_id": mid,
+            "memory": {
+                "id": str(memory["id"]),
+                "text": memory["text"],
+                "type": memory["fact_type"],
+                "context": memory["context"],
+            },
+        }
+
+        # Add chunk if available
+        if memory["chunk_id"] and memory["chunk_id"] in chunk_map:
+            chunk = chunk_map[memory["chunk_id"]]
+            item["chunk"] = {
+                "id": chunk["chunk_id"],
+                "text": chunk["chunk_text"],
+                "index": chunk["chunk_index"],
+                "document_id": chunk["document_id"],
+            }
+            # Add document if depth=document
+            if depth == "document" and chunk["document_id"] in doc_map:
+                doc = doc_map[chunk["document_id"]]
+                item["document"] = {
+                    "id": doc["id"],
+                    "full_text": doc["original_text"],
+                    "metadata": doc["metadata"],
+                    "retain_params": doc["retain_params"],
+                }
+        elif memory["document_id"] and depth == "document" and memory["document_id"] in doc_map:
+            # No chunk, but has document_id
+            doc = doc_map[memory["document_id"]]
+            item["document"] = {
+                "id": doc["id"],
+                "full_text": doc["original_text"],
+                "metadata": doc["metadata"],
+                "retain_params": doc["retain_params"],
+            }
+
+        results.append(item)
+
+    return {"results": results, "count": len(results)}

hindsight-api/hindsight_api/engine/reflect/tools_schema.py

@@ -0,0 +1,212 @@
+"""
+Tool schema definitions for the reflect agent.
+
+These are OpenAI-format tool definitions used with native tool calling.
+"""
+
+from typing import Literal
+
+# Tool definitions in OpenAI format
+TOOL_LIST_MENTAL_MODELS = {
+    "type": "function",
+    "function": {
+        "name": "list_mental_models",
+        "description": "List all available mental models - your synthesized knowledge about entities, concepts, and events. Returns an array of models with id, name, and description.",
+        "parameters": {
+            "type": "object",
+            "properties": {},
+            "required": [],
+        },
+    },
+}
+
+TOOL_GET_MENTAL_MODEL = {
+    "type": "function",
+    "function": {
+        "name": "get_mental_model",
+        "description": "Get full details of a specific mental model including all observations and memory references.",
+        "parameters": {
+            "type": "object",
+            "properties": {
+                "model_id": {
+                    "type": "string",
+                    "description": "ID of the mental model (from list_mental_models results)",
+                },
+            },
+            "required": ["model_id"],
+        },
+    },
+}
+
+TOOL_RECALL = {
+    "type": "function",
+    "function": {
+        "name": "recall",
+        "description": "Search memories using semantic + temporal retrieval. Returns relevant memories from experience and world knowledge, each with an 'id' you can reference.",
+        "parameters": {
+            "type": "object",
+            "properties": {
+                "query": {
+                    "type": "string",
+                    "description": "Search query string",
+                },
+                "max_tokens": {
+                    "type": "integer",
+                    "description": "Optional limit on result size (default 2048). Use higher values for broader searches.",
+                },
+            },
+            "required": ["query"],
+        },
+    },
+}
+
+TOOL_LEARN = {
+    "type": "function",
+    "function": {
+        "name": "learn",
+        "description": "Create a new mental model to track an important recurring topic. Use when you discover a person, project, concept, or pattern that appears frequently and would benefit from synthesized knowledge. The model content will be generated automatically.",
+        "parameters": {
+            "type": "object",
+            "properties": {
+                "name": {
+                    "type": "string",
+                    "description": "Human-readable name (e.g., 'Project Alpha', 'John Smith', 'Product Strategy')",
+                },
+                "description": {
+                    "type": "string",
+                    "description": "What to track and synthesize (e.g., 'Track goals, milestones, blockers, and key decisions for Project Alpha')",
+                },
+            },
+            "required": ["name", "description"],
+        },
+    },
+}
+
+TOOL_EXPAND = {
+    "type": "function",
+    "function": {
+        "name": "expand",
+        "description": "Get more context for one or more memories. Memory hierarchy: memory -> chunk -> document.",
+        "parameters": {
+            "type": "object",
+            "properties": {
+                "memory_ids": {
+                    "type": "array",
+                    "items": {"type": "string"},
+                    "description": "Array of memory IDs from recall results (batch multiple for efficiency)",
+                },
+                "depth": {
+                    "type": "string",
+                    "enum": ["chunk", "document"],
+                    "description": "chunk: surrounding text chunk, document: full source document",
+                },
+            },
+            "required": ["memory_ids", "depth"],
+        },
+    },
+}
+
+TOOL_DONE_ANSWER = {
+    "type": "function",
+    "function": {
+        "name": "done",
+        "description": "Signal completion with your final answer. Use this when you have gathered enough information to answer the question.",
+        "parameters": {
+            "type": "object",
+            "properties": {
+                "answer": {
+                    "type": "string",
+                    "description": "Your response as plain text. Do NOT use markdown formatting. NEVER include memory IDs, UUIDs, or 'Memory references' in this text - put IDs only in memory_ids array.",
+                },
+                "memory_ids": {
+                    "type": "array",
+                    "items": {"type": "string"},
+                    "description": "Array of memory IDs that support your answer (put IDs here, NOT in answer text)",
+                },
+                "model_ids": {
+                    "type": "array",
+                    "items": {"type": "string"},
+                    "description": "Array of mental model IDs that support your answer",
+                },
+            },
+            "required": ["answer"],
+        },
+    },
+}
+
+TOOL_DONE_OBSERVATIONS = {
+    "type": "function",
+    "function": {
+        "name": "done",
+        "description": "Signal completion with MULTIPLE structured observations. Each observation must be a SEPARATE item in the array covering ONE theme. Do NOT combine all content into a single observation.",
+        "parameters": {
+            "type": "object",
+            "properties": {
+                "observations": {
+                    "type": "array",
+                    "minItems": 3,
+                    "items": {
+                        "type": "object",
+                        "properties": {
+                            "title": {
+                                "type": "string",
+                                "description": "Short header for this observation's theme (e.g., 'Work Style', 'Technical Skills')",
+                            },
+                            "text": {
+                                "type": "string",
+                                "description": "Observation content about ONE theme. End with 'Key evidence:' containing text citations (summaries of what memories say), NOT memory IDs.",
+                            },
+                            "memory_ids": {
+                                "type": "array",
+                                "items": {"type": "string"},
+                                "description": "Full UUIDs of memories supporting this observation (put IDs here, not in text)",
+                            },
+                        },
+                        "required": ["title", "text", "memory_ids"],
+                    },
+                    "description": "Array of 3-8 observations, each covering a DIFFERENT aspect/theme. Do NOT put everything in one observation.",
+                },
+            },
+            "required": ["observations"],
+        },
+    },
+}
+
+
+def get_reflect_tools(
+    enable_learn: bool = True, output_mode: Literal["answer", "observations"] = "answer"
+) -> list[dict]:
+    """
+    Get the list of tools for the reflect agent.
+
+    Args:
+        enable_learn: Whether to include the learn tool
+        output_mode: "answer" or "observations" - determines done tool format
+                     In observations mode, mental model tools are excluded to avoid
+                     using potentially outdated models during regeneration.
+
+    Returns:
+        List of tool definitions in OpenAI format
+    """
+    tools = []
+
+    # In answer mode, include mental model tools for lookup
+    # In observations mode (mental model generation), exclude them to avoid circular references
+    if output_mode == "answer":
+        tools.append(TOOL_LIST_MENTAL_MODELS)
+        tools.append(TOOL_GET_MENTAL_MODEL)
+
+    tools.append(TOOL_RECALL)
+
+    if enable_learn:
+        tools.append(TOOL_LEARN)
+
+    tools.append(TOOL_EXPAND)
+
+    # Add appropriate done tool based on output mode
+    if output_mode == "observations":
+        tools.append(TOOL_DONE_OBSERVATIONS)
+    else:
+        tools.append(TOOL_DONE_ANSWER)
+
+    return tools

hindsight-api/hindsight_api/engine/response_models.py

@@ -10,8 +10,83 @@ from typing import Any
 
 from pydantic import BaseModel, ConfigDict, Field
 
-# Valid fact types for recall operations (excludes 'observation' which is internal)
-VALID_RECALL_FACT_TYPES = frozenset(["world", "experience", "opinion"])
+# Valid fact types for recall operations (excludes 'observation' which is internal, and 'opinion' which is deprecated)
+VALID_RECALL_FACT_TYPES = frozenset(["world", "experience"])
+
+
+class LLMToolCall(BaseModel):
+    """A tool call requested by the LLM."""
+
+    id: str = Field(description="Unique identifier for this tool call")
+    name: str = Field(description="Name of the tool to call")
+    arguments: dict[str, Any] = Field(description="Arguments to pass to the tool")
+
+
+class LLMToolCallResult(BaseModel):
+    """Result from an LLM call that may include tool calls."""
+
+    content: str | None = Field(default=None, description="Text content if any")
+    tool_calls: list[LLMToolCall] = Field(default_factory=list, description="Tool calls requested by the LLM")
+    finish_reason: str | None = Field(default=None, description="Reason the LLM stopped: 'stop', 'tool_calls', etc.")
+
+
+class ToolCallTrace(BaseModel):
+    """A single tool call made during reflect."""
+
+    tool: str = Field(description="Tool name: lookup, recall, learn, expand")
+    input: dict = Field(description="Tool input parameters")
+    output: dict = Field(description="Tool output/result")
+    duration_ms: int = Field(description="Execution time in milliseconds")
+    iteration: int = Field(default=0, description="Iteration number (1-based) when this tool was called")
+
+
+class LLMCallTrace(BaseModel):
+    """A single LLM call made during reflect."""
+
+    scope: str = Field(description="Call scope: agent_1, agent_2, final, etc.")
+    duration_ms: int = Field(description="Execution time in milliseconds")
+
+
+class MentalModelRef(BaseModel):
+    """Reference to a mental model accessed during reflect."""
+
+    id: str = Field(description="Mental model ID")
+    name: str = Field(description="Mental model name")
+    type: str = Field(description="Mental model type: entity, concept, event")
+    subtype: str = Field(description="Mental model subtype: structural, emergent, learned")
+    description: str = Field(description="Brief description")
+    summary: str | None = Field(default=None, description="Full summary (when looked up in detail)")
+
+
+class TokenUsage(BaseModel):
+    """
+    Token usage metrics for LLM calls.
+
+    Tracks input/output tokens for a single request to enable
+    per-request cost tracking and monitoring.
+    """
+
+    model_config = ConfigDict(
+        json_schema_extra={
+            "example": {
+                "input_tokens": 1500,
+                "output_tokens": 500,
+                "total_tokens": 2000,
+            }
+        }
+    )
+
+    input_tokens: int = Field(default=0, description="Number of input/prompt tokens consumed")
+    output_tokens: int = Field(default=0, description="Number of output/completion tokens generated")
+    total_tokens: int = Field(default=0, description="Total tokens (input + output)")
+
+    def __add__(self, other: "TokenUsage") -> "TokenUsage":
+        """Allow aggregating token usage from multiple calls."""
+        return TokenUsage(
+            input_tokens=self.input_tokens + other.input_tokens,
+            output_tokens=self.output_tokens + other.output_tokens,
+            total_tokens=self.total_tokens + other.total_tokens,
+        )
 
 
 class DispositionTraits(BaseModel):
@@ -54,6 +129,7 @@ class MemoryFact(BaseModel):
                 "metadata": {"source": "slack"},
                 "chunk_id": "bank123_session_abc123_0",
                 "activation": 0.95,
+                "tags": ["user_a", "session_123"],
             }
         }
     )
@@ -71,6 +147,7 @@ class MemoryFact(BaseModel):
     chunk_id: str | None = Field(
         None, description="ID of the chunk this fact was extracted from (format: bank_id_document_id_chunk_index)"
     )
+    tags: list[str] | None = Field(None, description="Visibility scope tags associated with this fact")
 
 
 class ChunkInfo(BaseModel):
@@ -123,7 +200,8 @@ class ReflectResult(BaseModel):
     Result from a reflect operation.
 
     Contains the formulated answer, the facts it was based on (organized by type),
-    and any new opinions that were formed during the reflection process.
+    any new opinions that were formed during the reflection process, and optionally
+    structured output if a response schema was provided.
     """
 
     model_config = ConfigDict(
@@ -145,6 +223,8 @@ class ReflectResult(BaseModel):
                     "opinion": [],
                 },
                 "new_opinions": ["Machine learning has great potential in healthcare"],
+                "structured_output": {"summary": "ML in healthcare", "confidence": 0.9},
+                "usage": {"input_tokens": 1500, "output_tokens": 500, "total_tokens": 2000},
             }
         }
     )
@@ -154,6 +234,26 @@ class ReflectResult(BaseModel):
         description="Facts used to formulate the answer, organized by type (world, experience, opinion)"
     )
     new_opinions: list[str] = Field(default_factory=list, description="List of newly formed opinions during reflection")
+    structured_output: dict[str, Any] | None = Field(
+        default=None,
+        description="Structured output parsed according to the provided response schema. Only present when response_schema was provided.",
+    )
+    usage: TokenUsage | None = Field(
+        default=None,
+        description="Token usage metrics for the LLM calls made during this reflect operation.",
+    )
+    tool_trace: list[ToolCallTrace] = Field(
+        default_factory=list,
+        description="Trace of tool calls made during reflection. Only present when include.tool_calls is enabled.",
+    )
+    llm_trace: list[LLMCallTrace] = Field(
+        default_factory=list,
+        description="Trace of LLM calls made during reflection. Only present when include.tool_calls is enabled.",
+    )
+    mental_models: list[MentalModelRef] = Field(
+        default_factory=list,
+        description="Mental models accessed during reflection. Only present when include.facts is enabled.",
+    )
 
 
 class Opinion(BaseModel):
@@ -217,3 +317,32 @@ class EntityState(BaseModel):
     observations: list[EntityObservation] = Field(
         default_factory=list, description="List of observations about this entity"
     )
+
+
+class MentalModel(BaseModel):
+    """
+    A manually configured mental model for tracking specific topics/areas.
+
+    Mental models are user-defined focus areas that the agent should track
+    and maintain summaries for, unlike auto-extracted entities.
+    """
+
+    model_config = ConfigDict(
+        json_schema_extra={
+            "example": {
+                "id": "team-dynamics",
+                "name": "Team Dynamics",
+                "description": "Track how the team collaborates, communication patterns, conflicts, and resolutions",
+                "summary": "The team has strong collaboration...",
+                "summary_updated_at": "2024-01-15T10:30:00Z",
+                "created_at": "2024-01-10T08:00:00Z",
+            }
+        }
+    )
+
+    id: str = Field(description="Unique identifier (alphanumeric lowercase)")
+    name: str = Field(description="Display name for the mental model")
+    description: str = Field(description="Prompt/directions for what to track and summarize")
+    summary: str | None = Field(None, description="Generated summary based on relevant facts")
+    summary_updated_at: str | None = Field(None, description="ISO format date when summary was last updated")
+    created_at: str = Field(description="ISO format date when the mental model was created")

hindsight-api/hindsight_api/engine/retain/bank_utils.py

@@ -1,5 +1,5 @@
 """
-bank profile utilities for disposition and background management.
+bank profile utilities for disposition and mission management.
 """
 
 import json
@@ -10,6 +10,7 @@ from typing import TypedDict
 from pydantic import BaseModel, Field
 
 from ..db_utils import acquire_with_retry
+from ..memory_engine import fq_table
 from ..response_models import DispositionTraits
 
 logger = logging.getLogger(__name__)
@@ -26,19 +27,18 @@ class BankProfile(TypedDict):
 
     name: str
     disposition: DispositionTraits
-    background: str
+    mission: str
 
 
-class BackgroundMergeResponse(BaseModel):
-    """LLM response for background merge with disposition inference."""
+class MissionMergeResponse(BaseModel):
+    """LLM response for mission merge."""
 
-    background: str = Field(description="Merged background in first person perspective")
-    disposition: DispositionTraits = Field(description="Inferred disposition traits (skepticism, literalism, empathy)")
+    mission: str = Field(description="Merged mission in first person perspective")
 
 
 async def get_bank_profile(pool, bank_id: str) -> BankProfile:
     """
-    Get bank profile (name, disposition + background).
+    Get bank profile (name, disposition + mission).
     Auto-creates bank with default values if not exists.
 
     Args:
@@ -46,14 +46,14 @@ async def get_bank_profile(pool, bank_id: str) -> BankProfile:
         bank_id: bank IDentifier
 
     Returns:
-        BankProfile with name, typed DispositionTraits, and background
+        BankProfile with name, typed DispositionTraits, and mission
     """
     async with acquire_with_retry(pool) as conn:
         # Try to get existing bank
         row = await conn.fetchrow(
-            """
-            SELECT name, disposition, background
-            FROM banks WHERE bank_id = $1
+            f"""
+            SELECT name, disposition, mission
+            FROM {fq_table("banks")} WHERE bank_id = $1
             """,
             bank_id,
         )
@@ -65,13 +65,15 @@ async def get_bank_profile(pool, bank_id: str) -> BankProfile:
                 disposition_data = json.loads(disposition_data)
 
             return BankProfile(
-                name=row["name"], disposition=DispositionTraits(**disposition_data), background=row["background"]
+                name=row["name"],
+                disposition=DispositionTraits(**disposition_data),
+                mission=row["mission"] or "",
             )
 
         # Bank doesn't exist, create with defaults
         await conn.execute(
-            """
-            INSERT INTO banks (bank_id, name, disposition, background)
+            f"""
+            INSERT INTO {fq_table("banks")} (bank_id, name, disposition, mission)
             VALUES ($1, $2, $3::jsonb, $4)
             ON CONFLICT (bank_id) DO NOTHING
             """,
@@ -81,7 +83,7 @@ async def get_bank_profile(pool, bank_id: str) -> BankProfile:
             "",
         )
 
-        return BankProfile(name=bank_id, disposition=DispositionTraits(**DEFAULT_DISPOSITION), background="")
+        return BankProfile(name=bank_id, disposition=DispositionTraits(**DEFAULT_DISPOSITION), mission="")
 
 
 async def update_bank_disposition(pool, bank_id: str, disposition: dict[str, int]) -> None:
@@ -98,8 +100,8 @@ async def update_bank_disposition(pool, bank_id: str, disposition: dict[str, int
 
     async with acquire_with_retry(pool) as conn:
         await conn.execute(
-            """
-            UPDATE banks
+            f"""
+            UPDATE {fq_table("banks")}
             SET disposition = $2::jsonb,
                 updated_at = NOW()
             WHERE bank_id = $1
@@ -109,244 +111,121 @@ async def update_bank_disposition(pool, bank_id: str, disposition: dict[str, int
         )
 
 
-async def merge_bank_background(pool, llm_config, bank_id: str, new_info: str, update_disposition: bool = True) -> dict:
+async def set_bank_mission(pool, bank_id: str, mission: str) -> None:
     """
-    Merge new background information with existing background using LLM.
-    Normalizes to first person ("I") and resolves conflicts.
-    Optionally infers disposition traits from the merged background.
+    Set bank mission (replacing any existing mission).
 
     Args:
         pool: Database connection pool
-        llm_config: LLM configuration for background merging
         bank_id: bank IDentifier
-        new_info: New background information to add/merge
-        update_disposition: If True, infer Big Five traits from background (default: True)
+        mission: The mission text
+    """
+    # Ensure bank exists first
+    await get_bank_profile(pool, bank_id)
+
+    async with acquire_with_retry(pool) as conn:
+        await conn.execute(
+            f"""
+            UPDATE {fq_table("banks")}
+            SET mission = $2,
+                updated_at = NOW()
+            WHERE bank_id = $1
+            """,
+            bank_id,
+            mission,
+        )
+
+
+async def merge_bank_mission(pool, llm_config, bank_id: str, new_info: str) -> dict:
+    """
+    Merge new mission information with existing mission using LLM.
+    Normalizes to first person ("I") and resolves conflicts.
+
+    Args:
+        pool: Database connection pool
+        llm_config: LLM configuration for mission merging
+        bank_id: bank IDentifier
+        new_info: New mission information to add/merge
 
     Returns:
-        Dict with 'background' (str) and optionally 'disposition' (dict) keys
+        Dict with 'mission' (str) key
     """
     # Get current profile
     profile = await get_bank_profile(pool, bank_id)
-    current_background = profile["background"]
+    current_mission = profile["mission"]
 
-    # Use LLM to merge backgrounds and optionally infer disposition
-    result = await _llm_merge_background(llm_config, current_background, new_info, infer_disposition=update_disposition)
+    # Use LLM to merge missions
+    result = await _llm_merge_mission(llm_config, current_mission, new_info)
 
-    merged_background = result["background"]
-    inferred_disposition = result.get("disposition")
+    merged_mission = result["mission"]
 
     # Update in database
     async with acquire_with_retry(pool) as conn:
-        if inferred_disposition:
-            # Update both background and disposition
-            await conn.execute(
-                """
-                UPDATE banks
-                SET background = $2,
-                    disposition = $3::jsonb,
-                    updated_at = NOW()
-                WHERE bank_id = $1
-                """,
-                bank_id,
-                merged_background,
-                json.dumps(inferred_disposition),
-            )
-        else:
-            # Update only background
-            await conn.execute(
-                """
-                UPDATE banks
-                SET background = $2,
-                    updated_at = NOW()
-                WHERE bank_id = $1
-                """,
-                bank_id,
-                merged_background,
-            )
+        await conn.execute(
+            f"""
+            UPDATE {fq_table("banks")}
+            SET mission = $2,
+                updated_at = NOW()
+            WHERE bank_id = $1
+            """,
+            bank_id,
+            merged_mission,
+        )
 
-    response = {"background": merged_background}
-    if inferred_disposition:
-        response["disposition"] = inferred_disposition
-
-    return response
+    return {"mission": merged_mission}
 
 
-async def _llm_merge_background(llm_config, current: str, new_info: str, infer_disposition: bool = False) -> dict:
+async def _llm_merge_mission(llm_config, current: str, new_info: str) -> dict:
     """
-    Use LLM to intelligently merge background information.
-    Optionally infer Big Five disposition traits from the merged background.
+    Use LLM to intelligently merge mission information.
 
     Args:
         llm_config: LLM configuration to use
-        current: Current background text
+        current: Current mission text
         new_info: New information to merge
-        infer_disposition: If True, also infer disposition traits
 
     Returns:
-        Dict with 'background' (str) and optionally 'disposition' (dict) keys
+        Dict with 'mission' (str) key
     """
-    if infer_disposition:
-        prompt = f"""You are helping maintain a memory bank's background/profile and infer their disposition. You MUST respond with ONLY valid JSON.
+    prompt = f"""You are helping maintain an agent's mission statement.
 
-Current background: {current if current else "(empty)"}
+Current mission: {current if current else "(empty)"}
 
 New information to add: {new_info}
 
 Instructions:
-1. Merge the new information with the current background
-2. If there are conflicts (e.g., different birthplaces), the NEW information overwrites the old
-3. Keep additions that don't conflict
-4. Output in FIRST PERSON ("I") perspective
-5. Be concise - keep merged background under 500 characters
-6. Infer disposition traits from the merged background (each 1-5 integer):
-   - Skepticism: 1-5 (1=trusting, takes things at face value; 5=skeptical, questions everything)
-   - Literalism: 1-5 (1=flexible interpretation, reads between lines; 5=literal, exact interpretation)
-   - Empathy: 1-5 (1=detached, focuses on facts; 5=empathetic, considers emotional context)
-
-CRITICAL: You MUST respond with ONLY a valid JSON object. No markdown, no code blocks, no explanations. Just the JSON.
-
-Format:
-{{
-  "background": "the merged background text in first person",
-  "disposition": {{
-    "skepticism": 3,
-    "literalism": 3,
-    "empathy": 3
-  }}
-}}
-
-Trait inference examples:
-- "I'm a lawyer" → skepticism: 4, literalism: 5, empathy: 2
-- "I'm a therapist" → skepticism: 2, literalism: 2, empathy: 5
-- "I'm an engineer" → skepticism: 3, literalism: 4, empathy: 3
-- "I've been burned before by trusting people" → skepticism: 5, literalism: 3, empathy: 3
-- "I try to understand what people really mean" → skepticism: 3, literalism: 2, empathy: 4
-- "I take contracts very seriously" → skepticism: 4, literalism: 5, empathy: 2"""
-    else:
-        prompt = f"""You are helping maintain a memory bank's background/profile.
-
-Current background: {current if current else "(empty)"}
-
-New information to add: {new_info}
-
-Instructions:
-1. Merge the new information with the current background
-2. If there are conflicts (e.g., different birthplaces), the NEW information overwrites the old
+1. Merge the new information with the current mission
+2. If there are conflicts, the NEW information overwrites the old
 3. Keep additions that don't conflict
 4. Output in FIRST PERSON ("I") perspective
 5. Be concise - keep it under 500 characters
-6. Return ONLY the merged background text, no explanations
+6. Return ONLY the merged mission text, no explanations
 
-Merged background:"""
+Merged mission:"""
 
     try:
-        # Prepare messages
         messages = [{"role": "user", "content": prompt}]
 
-        if infer_disposition:
-            # Use structured output with Pydantic model for disposition inference
-            try:
-                parsed = await llm_config.call(
-                    messages=messages,
-                    response_format=BackgroundMergeResponse,
-                    scope="bank_background",
-                    temperature=0.3,
-                    max_completion_tokens=8192,
-                )
-                logger.info(f"Successfully got structured response: background={parsed.background[:100]}")
-
-                # Convert Pydantic model to dict format
-                return {"background": parsed.background, "disposition": parsed.disposition.model_dump()}
-            except Exception as e:
-                logger.warning(f"Structured output failed, falling back to manual parsing: {e}")
-                # Fall through to manual parsing below
-
-        # Manual parsing fallback or non-disposition merge
         content = await llm_config.call(
-            messages=messages, scope="bank_background", temperature=0.3, max_completion_tokens=8192
+            messages=messages, scope="bank_mission", temperature=0.3, max_completion_tokens=8192
         )
 
-        logger.info(f"LLM response for background merge (first 500 chars): {content[:500]}")
+        logger.info(f"LLM response for mission merge (first 500 chars): {content[:500]}")
 
-        if infer_disposition:
-            # Parse JSON response - try multiple extraction methods
-            result = None
-
-            # Method 1: Direct parse
-            try:
-                result = json.loads(content)
-                logger.info("Successfully parsed JSON directly")
-            except json.JSONDecodeError:
-                pass
-
-            # Method 2: Extract from markdown code blocks
-            if result is None:
-                # Remove markdown code blocks
-                code_block_match = re.search(r"```(?:json)?\s*(\{.*?\})\s*```", content, re.DOTALL)
-                if code_block_match:
-                    try:
-                        result = json.loads(code_block_match.group(1))
-                        logger.info("Successfully extracted JSON from markdown code block")
-                    except json.JSONDecodeError:
-                        pass
-
-            # Method 3: Find nested JSON structure
-            if result is None:
-                # Look for JSON object with nested structure
-                json_match = re.search(
-                    r'\{[^{}]*"background"[^{}]*"disposition"[^{}]*\{[^{}]*\}[^{}]*\}', content, re.DOTALL
-                )
-                if json_match:
-                    try:
-                        result = json.loads(json_match.group())
-                        logger.info("Successfully extracted JSON using nested pattern")
-                    except json.JSONDecodeError:
-                        pass
-
-            # All parsing methods failed - use fallback
-            if result is None:
-                logger.warning(f"Failed to extract JSON from LLM response. Raw content: {content[:200]}")
-                # Fallback: use new_info as background with default disposition
-                return {
-                    "background": new_info if new_info else current if current else "",
-                    "disposition": DEFAULT_DISPOSITION.copy(),
-                }
-
-            # Validate disposition values
-            disposition = result.get("disposition", {})
-            for key in ["skepticism", "literalism", "empathy"]:
-                if key not in disposition:
-                    disposition[key] = 3  # Default to neutral
-                else:
-                    # Clamp to [1, 5] and convert to int
-                    disposition[key] = max(1, min(5, int(disposition[key])))
-
-            result["disposition"] = disposition
-
-            # Ensure background exists
-            if "background" not in result or not result["background"]:
-                result["background"] = new_info if new_info else ""
-
-            return result
-        else:
-            # Just background merge
-            merged = content
-            if not merged or merged.lower() in ["(empty)", "none", "n/a"]:
-                merged = new_info if new_info else ""
-            return {"background": merged}
+        merged = content.strip()
+        if not merged or merged.lower() in ["(empty)", "none", "n/a"]:
+            merged = new_info if new_info else ""
+        return {"mission": merged}
 
     except Exception as e:
-        logger.error(f"Error merging background with LLM: {e}")
+        logger.error(f"Error merging mission with LLM: {e}")
         # Fallback: just append new info
         if current:
             merged = f"{current} {new_info}".strip()
         else:
             merged = new_info
 
-        result = {"background": merged}
-        if infer_disposition:
-            result["disposition"] = DEFAULT_DISPOSITION.copy()
-        return result
+        return {"mission": merged}
 
 
 async def list_banks(pool) -> list:
@@ -357,13 +236,13 @@ async def list_banks(pool) -> list:
         pool: Database connection pool
 
     Returns:
-        List of dicts with bank_id, name, disposition, background, created_at, updated_at
+        List of dicts with bank_id, name, disposition, mission, created_at, updated_at
     """
     async with acquire_with_retry(pool) as conn:
         rows = await conn.fetch(
-            """
-            SELECT bank_id, name, disposition, background, created_at, updated_at
-            FROM banks
+            f"""
+            SELECT bank_id, name, disposition, mission, created_at, updated_at
+            FROM {fq_table("banks")}
             ORDER BY updated_at DESC
             """
         )
@@ -380,7 +259,7 @@ async def list_banks(pool) -> list:
                     "bank_id": row["bank_id"],
                     "name": row["name"],
                     "disposition": disposition_data,
-                    "background": row["background"],
+                    "mission": row["mission"] or "",
                     "created_at": row["created_at"].isoformat() if row["created_at"] else None,
                     "updated_at": row["updated_at"].isoformat() if row["updated_at"] else None,
                 }

hindsight-api/hindsight_api/engine/retain/chunk_storage.py

@@ -6,6 +6,7 @@ Handles storage of document chunks in the database.
 
 import logging
 
+from ..memory_engine import fq_table
 from .types import ChunkMetadata
 
 logger = logging.getLogger(__name__)
@@ -42,8 +43,8 @@ async def store_chunks_batch(conn, bank_id: str, document_id: str, chunks: list[
 
     # Batch insert all chunks
     await conn.execute(
-        """
-        INSERT INTO chunks (chunk_id, document_id, bank_id, chunk_text, chunk_index)
+        f"""
+        INSERT INTO {fq_table("chunks")} (chunk_id, document_id, bank_id, chunk_text, chunk_index)
         SELECT * FROM unnest($1::text[], $2::text[], $3::text[], $4::text[], $5::integer[])
         """,
         chunk_ids,

hindsight-api/hindsight_api/engine/retain/entity_processing.py

@@ -13,16 +13,23 @@ logger = logging.getLogger(__name__)
 
 
 async def process_entities_batch(
-    entity_resolver, conn, bank_id: str, unit_ids: list[str], facts: list[ProcessedFact], log_buffer: list[str] = None
+    entity_resolver,
+    conn,
+    bank_id: str,
+    unit_ids: list[str],
+    facts: list[ProcessedFact],
+    log_buffer: list[str] = None,
+    user_entities_per_content: dict[int, list[dict]] = None,
 ) -> list[EntityLink]:
     """
     Process entities for all facts and create entity links.
 
     This function:
     1. Extracts entity mentions from fact texts
-    2. Resolves entity names to canonical entities
-    3. Creates entity records in the database
-    4. Returns entity links ready for insertion
+    2. Merges user-provided entities with LLM-extracted entities
+    3. Resolves entity names to canonical entities
+    4. Creates entity records in the database
+    5. Returns entity links ready for insertion
 
     Args:
         entity_resolver: EntityResolver instance for entity resolution
@@ -31,6 +38,7 @@ async def process_entities_batch(
         unit_ids: List of unit IDs (same length as facts)
         facts: List of ProcessedFact objects
         log_buffer: Optional buffer for detailed logging
+        user_entities_per_content: Dict mapping content_index to list of user-provided entities
 
     Returns:
         List of EntityLink objects for batch insertion
@@ -41,14 +49,35 @@ async def process_entities_batch(
     if len(unit_ids) != len(facts):
         raise ValueError(f"Mismatch between unit_ids ({len(unit_ids)}) and facts ({len(facts)})")
 
+    user_entities_per_content = user_entities_per_content or {}
+
     # Extract data for link_utils function
     fact_texts = [fact.fact_text for fact in facts]
     # Use occurred_start if available, otherwise use mentioned_at for entity timestamps
     fact_dates = [fact.occurred_start if fact.occurred_start is not None else fact.mentioned_at for fact in facts]
-    # Convert EntityRef objects to dict format expected by link_utils
-    entities_per_fact = [
-        [{"text": entity.name, "type": "CONCEPT"} for entity in (fact.entities or [])] for fact in facts
-    ]
+
+    # Convert EntityRef objects to dict format and merge with user-provided entities
+    entities_per_fact = []
+    for fact in facts:
+        # Start with LLM-extracted entities
+        llm_entities = [{"text": entity.name, "type": "CONCEPT"} for entity in (fact.entities or [])]
+
+        # Get user entities for this content (use content_index from fact)
+        user_entities = user_entities_per_content.get(fact.content_index, [])
+
+        # Merge with case-insensitive deduplication
+        seen_texts = {e["text"].lower() for e in llm_entities}
+        for user_entity in user_entities:
+            if user_entity["text"].lower() not in seen_texts:
+                llm_entities.append(
+                    {
+                        "text": user_entity["text"],
+                        "type": user_entity.get("type", "CONCEPT"),
+                    }
+                )
+                seen_texts.add(user_entity["text"].lower())
+
+        entities_per_fact.append(llm_entities)
 
     # Use existing link_utils function for entity processing
     entity_links = await link_utils.extract_entities_batch_optimized(

hindsight-api/hindsight_api/engine/retain/fact_extraction.py

@@ -14,7 +14,47 @@ from typing import Literal
 
 from pydantic import BaseModel, ConfigDict, Field, field_validator
 
+from ...config import get_config
 from ..llm_wrapper import LLMConfig, OutputTooLongError
+from ..response_models import TokenUsage
+
+
+def _infer_temporal_date(fact_text: str, event_date: datetime) -> str | None:
+    """
+    Infer a temporal date from fact text when LLM didn't provide occurred_start.
+
+    This is a fallback for when the LLM fails to extract temporal information
+    from relative time expressions like "last night", "yesterday", etc.
+    """
+    import re
+
+    fact_lower = fact_text.lower()
+
+    # Map relative time expressions to day offsets
+    temporal_patterns = {
+        r"\blast night\b": -1,
+        r"\byesterday\b": -1,
+        r"\btoday\b": 0,
+        r"\bthis morning\b": 0,
+        r"\bthis afternoon\b": 0,
+        r"\bthis evening\b": 0,
+        r"\btonigh?t\b": 0,
+        r"\btomorrow\b": 1,
+        r"\blast week\b": -7,
+        r"\bthis week\b": 0,
+        r"\bnext week\b": 7,
+        r"\blast month\b": -30,
+        r"\bthis month\b": 0,
+        r"\bnext month\b": 30,
+    }
+
+    for pattern, offset_days in temporal_patterns.items():
+        if re.search(pattern, fact_lower):
+            target_date = event_date + timedelta(days=offset_days)
+            return target_date.replace(hour=0, minute=0, second=0, microsecond=0).isoformat()
+
+    # If no relative time expression found, return None
+    return None
 
 
 def _sanitize_text(text: str) -> str:
@@ -71,22 +111,44 @@ class Fact(BaseModel):
 
 
 class CausalRelation(BaseModel):
-    """Causal relationship between facts."""
+    """Causal relationship from this fact to a previous fact (stored format)."""
 
-    target_fact_index: int = Field(
-        description="Index of the related fact in the facts array (0-based). "
-        "This creates a directed causal link to another fact in the extraction."
-    )
-    relation_type: Literal["causes", "caused_by", "enables", "prevents"] = Field(
-        description="Type of causal relationship: "
-        "'causes' = this fact directly causes the target fact, "
-        "'caused_by' = this fact was caused by the target fact, "
-        "'enables' = this fact enables/allows the target fact, "
-        "'prevents' = this fact prevents/blocks the target fact"
+    target_fact_index: int = Field(description="Index of the related fact in the facts array (0-based).")
+    relation_type: Literal["caused_by", "enabled_by", "prevented_by"] = Field(
+        description="How this fact relates to the target: "
+        "'caused_by' = this fact was caused by the target, "
+        "'enabled_by' = this fact was enabled by the target, "
+        "'prevented_by' = this fact was prevented by the target"
     )
     strength: float = Field(
-        description="Strength of causal relationship (0.0 to 1.0). "
-        "1.0 = direct/strong causation, 0.5 = moderate, 0.3 = weak/indirect",
+        description="Strength of relationship (0.0 to 1.0)",
+        ge=0.0,
+        le=1.0,
+        default=1.0,
+    )
+
+
+class FactCausalRelation(BaseModel):
+    """
+    Causal relationship from this fact to a PREVIOUS fact (embedded in each fact).
+
+    Uses index-based references but ONLY allows referencing facts that appear
+    BEFORE this fact in the list. This prevents hallucination of invalid indices.
+    """
+
+    target_index: int = Field(
+        description="Index of the PREVIOUS fact this relates to (0-based). "
+        "MUST be less than this fact's position in the list. "
+        "Example: if this is fact #5, target_index can only be 0, 1, 2, 3, or 4."
+    )
+    relation_type: Literal["caused_by", "enabled_by", "prevented_by"] = Field(
+        description="How this fact relates to the target fact: "
+        "'caused_by' = this fact was caused by the target fact, "
+        "'enabled_by' = this fact was enabled by the target fact, "
+        "'prevented_by' = this fact was blocked/prevented by the target fact"
+    )
+    strength: float = Field(
+        description="Strength of relationship (0.0 to 1.0). 1.0 = strong, 0.5 = moderate",
         ge=0.0,
         le=1.0,
         default=1.0,
@@ -94,16 +156,67 @@ class CausalRelation(BaseModel):
 
 
 class ExtractedFact(BaseModel):
-    """A single extracted fact with 5 required dimensions for comprehensive capture."""
+    """A single extracted fact."""
 
     model_config = ConfigDict(
         json_schema_mode="validation",
         json_schema_extra={"required": ["what", "when", "where", "who", "why", "fact_type"]},
     )
 
-    # ==========================================================================
-    # FIVE REQUIRED DIMENSIONS - LLM must think about each one
-    # ==========================================================================
+    what: str = Field(description="Core fact - concise but complete (1-2 sentences)")
+    when: str = Field(description="When it happened. 'N/A' if unknown.")
+    where: str = Field(description="Location if relevant. 'N/A' if none.")
+    who: str = Field(description="People involved with relationships. 'N/A' if general.")
+    why: str = Field(description="Context/significance if important. 'N/A' if obvious.")
+
+    fact_kind: str = Field(default="conversation", description="'event' or 'conversation'")
+    occurred_start: str | None = Field(default=None, description="ISO timestamp for events")
+    occurred_end: str | None = Field(default=None, description="ISO timestamp for event end")
+    fact_type: Literal["world", "assistant"] = Field(description="'world' or 'assistant'")
+    entities: list[Entity] | None = Field(default=None, description="People, places, concepts")
+    causal_relations: list[FactCausalRelation] | None = Field(
+        default=None, description="Links to previous facts (target_index < this fact's index)"
+    )
+
+    @field_validator("entities", mode="before")
+    @classmethod
+    def ensure_entities_list(cls, v):
+        """Ensure entities is always a list (convert None to empty list)."""
+        if v is None:
+            return []
+        return v
+
+    def build_fact_text(self) -> str:
+        """Combine all dimensions into a single comprehensive fact string."""
+        parts = [self.what]
+
+        # Add 'who' if not N/A
+        if self.who and self.who.upper() != "N/A":
+            parts.append(f"Involving: {self.who}")
+
+        # Add 'why' if not N/A
+        if self.why and self.why.upper() != "N/A":
+            parts.append(self.why)
+
+        if len(parts) == 1:
+            return parts[0]
+
+        return " | ".join(parts)
+
+
+class FactExtractionResponse(BaseModel):
+    """Response containing all extracted facts (causal relations are embedded in each fact)."""
+
+    facts: list[ExtractedFact] = Field(description="List of extracted factual statements")
+
+
+class ExtractedFactVerbose(BaseModel):
+    """A single extracted fact with verbose field descriptions for detailed extraction."""
+
+    model_config = ConfigDict(
+        json_schema_mode="validation",
+        json_schema_extra={"required": ["what", "when", "where", "who", "why", "fact_type"]},
+    )
 
     what: str = Field(
         description="WHAT happened - COMPLETE, DETAILED description with ALL specifics. "
@@ -146,16 +259,11 @@ class ExtractedFact(BaseModel):
         "NOT: 'User liked it' or 'To help user'"
     )
 
-    # ==========================================================================
-    # CLASSIFICATION
-    # ==========================================================================
-
     fact_kind: str = Field(
         default="conversation",
         description="'event' = specific datable occurrence (set occurred dates), 'conversation' = general info (no occurred dates)",
     )
 
-    # Temporal fields - optional
     occurred_start: str | None = Field(
         default=None,
         description="WHEN the event happened (ISO timestamp). Only for fact_kind='event'. Leave null for conversations.",
@@ -165,59 +273,76 @@ class ExtractedFact(BaseModel):
         description="WHEN the event ended (ISO timestamp). Only for events with duration. Leave null for conversations.",
     )
 
-    # Classification (CRITICAL - required)
-    # Note: LLM uses "assistant" but we convert to "bank" for storage
     fact_type: Literal["world", "assistant"] = Field(
         description="'world' = about the user/others (background, experiences). 'assistant' = experience with the assistant."
     )
 
-    # Entities - extracted from fact content
     entities: list[Entity] | None = Field(
         default=None,
         description="Named entities, objects, AND abstract concepts from the fact. Include: people names, organizations, places, significant objects (e.g., 'coffee maker', 'car'), AND abstract concepts/themes (e.g., 'friendship', 'career growth', 'loss', 'celebration'). Extract anything that could help link related facts together.",
     )
-    causal_relations: list[CausalRelation] | None = Field(
-        default=None, description="Causal links to other facts. Can be null."
+
+    causal_relations: list[FactCausalRelation] | None = Field(
+        default=None,
+        description="Causal links to PREVIOUS facts only. target_index MUST be less than this fact's position. "
+        "Example: fact #3 can only reference facts 0, 1, or 2. Max 2 relations per fact.",
     )
 
     @field_validator("entities", mode="before")
     @classmethod
     def ensure_entities_list(cls, v):
-        """Ensure entities is always a list (convert None to empty list)."""
         if v is None:
             return []
         return v
 
-    @field_validator("causal_relations", mode="before")
+
+class FactExtractionResponseVerbose(BaseModel):
+    """Response for verbose fact extraction."""
+
+    facts: list[ExtractedFactVerbose] = Field(description="List of extracted factual statements")
+
+
+class ExtractedFactNoCausal(BaseModel):
+    """A single extracted fact WITHOUT causal relations (for when causal extraction is disabled)."""
+
+    model_config = ConfigDict(
+        json_schema_mode="validation",
+        json_schema_extra={"required": ["what", "when", "where", "who", "why", "fact_type"]},
+    )
+
+    # Same fields as ExtractedFact but without causal_relations
+    what: str = Field(description="WHAT happened - COMPLETE, DETAILED description with ALL specifics.")
+    when: str = Field(description="WHEN it happened - include temporal information if mentioned.")
+    where: str = Field(description="WHERE it happened - SPECIFIC locations if applicable.")
+    who: str = Field(description="WHO is involved - ALL people/entities with relationships.")
+    why: str = Field(description="WHY it matters - emotional, contextual, and motivational details.")
+
+    fact_kind: str = Field(
+        default="conversation",
+        description="'event' = specific datable occurrence, 'conversation' = general info",
+    )
+    occurred_start: str | None = Field(default=None, description="WHEN the event happened (ISO timestamp).")
+    occurred_end: str | None = Field(default=None, description="WHEN the event ended (ISO timestamp).")
+    fact_type: Literal["world", "assistant"] = Field(
+        description="'world' = about the user/others. 'assistant' = experience with assistant."
+    )
+    entities: list[Entity] | None = Field(
+        default=None,
+        description="Named entities, objects, and concepts from the fact.",
+    )
+
+    @field_validator("entities", mode="before")
     @classmethod
-    def ensure_causal_relations_list(cls, v):
-        """Ensure causal_relations is always a list (convert None to empty list)."""
+    def ensure_entities_list(cls, v):
         if v is None:
             return []
         return v
 
-    def build_fact_text(self) -> str:
-        """Combine all dimensions into a single comprehensive fact string."""
-        parts = [self.what]
 
-        # Add 'who' if not N/A
-        if self.who and self.who.upper() != "N/A":
-            parts.append(f"Involving: {self.who}")
+class FactExtractionResponseNoCausal(BaseModel):
+    """Response for fact extraction without causal relations."""
 
-        # Add 'why' if not N/A
-        if self.why and self.why.upper() != "N/A":
-            parts.append(self.why)
-
-        if len(parts) == 1:
-            return parts[0]
-
-        return " | ".join(parts)
-
-
-class FactExtractionResponse(BaseModel):
-    """Response containing all extracted facts."""
-
-    facts: list[ExtractedFact] = Field(description="List of extracted factual statements")
+    facts: list[ExtractedFactNoCausal] = Field(description="List of extracted factual statements")
 
 
 def chunk_text(text: str, max_chars: int) -> list[str]:
@@ -309,39 +434,119 @@ def _chunk_conversation(turns: list[dict], max_chars: int) -> list[str]:
     return chunks if chunks else [json.dumps(turns, ensure_ascii=False)]
 
 
-async def _extract_facts_from_chunk(
-    chunk: str,
-    chunk_index: int,
-    total_chunks: int,
-    event_date: datetime,
-    context: str,
-    llm_config: "LLMConfig",
-    agent_name: str = None,
-    extract_opinions: bool = False,
-) -> list[dict[str, str]]:
-    """
-    Extract facts from a single chunk (internal helper for parallel processing).
+# =============================================================================
+# FACT EXTRACTION PROMPTS
+# =============================================================================
 
-    Note: event_date parameter is kept for backward compatibility but not used in prompt.
-    The LLM extracts temporal information from the context string instead.
-    """
-    memory_bank_context = f"\n- Your name: {agent_name}" if agent_name and extract_opinions else ""
+# Concise extraction prompt (default) - selective, high-quality facts
+CONCISE_FACT_EXTRACTION_PROMPT = """Extract SIGNIFICANT facts from text. Be SELECTIVE - only extract facts worth remembering long-term.
 
-    # Determine which fact types to extract based on the flag
-    # Note: We use "assistant" in the prompt but convert to "bank" for storage
-    if extract_opinions:
-        # Opinion extraction uses a separate prompt (not this one)
-        fact_types_instruction = "Extract ONLY 'opinion' type facts (formed opinions, beliefs, and perspectives). DO NOT extract 'world' or 'assistant' facts."
-    else:
-        fact_types_instruction = (
-            "Extract ONLY 'world' and 'assistant' type facts. DO NOT extract opinions - those are extracted separately."
-        )
-
-    prompt = f"""Extract facts from text into structured format with FOUR required dimensions - BE EXTREMELY DETAILED.
+LANGUAGE RULE (CRITICAL): Output facts in the EXACT SAME language as the input text. If input is Japanese, output Japanese. If input is Chinese, output Chinese. NEVER translate to English. Preserve original language completely.
 
 {fact_types_instruction}
 
+══════════════════════════════════════════════════════════════════════════
+SELECTIVITY - CRITICAL (Reduces 90% of unnecessary output)
+══════════════════════════════════════════════════════════════════════════
 
+ONLY extract facts that are:
+✅ Personal info: names, relationships, roles, background
+✅ Preferences: likes, dislikes, habits, interests (e.g., "Alice likes coffee")
+✅ Significant events: milestones, decisions, achievements, changes
+✅ Plans/goals: future intentions, deadlines, commitments
+✅ Expertise: skills, knowledge, certifications, experience
+✅ Important context: projects, problems, constraints
+✅ Sensory/emotional details: feelings, sensations, perceptions that provide context
+✅ Observations: descriptions of people, places, things with specific details
+
+DO NOT extract:
+❌ Generic greetings: "how are you", "hello", pleasantries without substance
+❌ Pure filler: "thanks", "sounds good", "ok", "got it", "sure"
+❌ Process chatter: "let me check", "one moment", "I'll look into it"
+❌ Repeated info: if already stated, don't extract again
+
+CONSOLIDATE related statements into ONE fact when possible.
+
+══════════════════════════════════════════════════════════════════════════
+FACT FORMAT - BE CONCISE
+══════════════════════════════════════════════════════════════════════════
+
+1. **what**: Core fact - concise but complete (1-2 sentences max)
+2. **when**: Temporal info if mentioned. "N/A" if none. Use day name when known.
+3. **where**: Location if relevant. "N/A" if none.
+4. **who**: People involved with relationships. "N/A" if just general info.
+5. **why**: Context/significance ONLY if important. "N/A" if obvious.
+
+CONCISENESS: Capture the essence, not every word. One good sentence beats three mediocre ones.
+
+══════════════════════════════════════════════════════════════════════════
+COREFERENCE RESOLUTION
+══════════════════════════════════════════════════════════════════════════
+
+Link generic references to names when both appear:
+- "my roommate" + "Emily" → use "Emily (user's roommate)"
+- "the manager" + "Sarah" → use "Sarah (the manager)"
+
+══════════════════════════════════════════════════════════════════════════
+CLASSIFICATION
+══════════════════════════════════════════════════════════════════════════
+
+fact_kind:
+- "event": Specific datable occurrence (set occurred_start/end)
+- "conversation": Ongoing state, preference, trait (no dates)
+
+fact_type:
+- "world": About user's life, other people, external events
+- "assistant": Interactions with assistant (requests, recommendations)
+
+══════════════════════════════════════════════════════════════════════════
+TEMPORAL HANDLING
+══════════════════════════════════════════════════════════════════════════
+
+Use "Event Date" from input as reference for relative dates.
+- "yesterday" relative to Event Date, not today
+- For events: set occurred_start AND occurred_end (same for point events)
+- For conversation facts: NO occurred dates
+
+══════════════════════════════════════════════════════════════════════════
+ENTITIES
+══════════════════════════════════════════════════════════════════════════
+
+Include: people names, organizations, places, key objects, abstract concepts (career, friendship, etc.)
+Always include "user" when fact is about the user.
+
+══════════════════════════════════════════════════════════════════════════
+EXAMPLES
+══════════════════════════════════════════════════════════════════════════
+
+Example 1 - Selective extraction (Event Date: June 10, 2024):
+Input: "Hey! How's it going? Good morning! So I'm planning my wedding - want a small outdoor ceremony. Just got back from Emily's wedding, she married Sarah at a rooftop garden. It was nice weather. I grabbed a coffee on the way."
+
+Output: ONLY 2 facts (skip greetings, weather, coffee):
+1. what="User planning wedding, wants small outdoor ceremony", who="user", why="N/A", entities=["user", "wedding"]
+2. what="Emily married Sarah at rooftop garden", who="Emily (user's friend), Sarah", occurred_start="2024-06-09", entities=["Emily", "Sarah", "wedding"]
+
+Example 2 - Professional context:
+Input: "Alice has 5 years of Kubernetes experience and holds CKA certification. She's been leading the infrastructure team since March. By the way, she prefers dark roast coffee."
+
+Output: ONLY 2 facts (skip coffee preference - too trivial):
+1. what="Alice has 5 years Kubernetes experience, CKA certified", who="Alice", entities=["Alice", "Kubernetes", "CKA"]
+2. what="Alice leads infrastructure team since March", who="Alice", entities=["Alice", "infrastructure"]
+
+══════════════════════════════════════════════════════════════════════════
+QUALITY OVER QUANTITY
+══════════════════════════════════════════════════════════════════════════
+
+Ask: "Would this be useful to recall in 6 months?" If no, skip it."""
+
+
+# Verbose extraction prompt - detailed, comprehensive facts (legacy mode)
+VERBOSE_FACT_EXTRACTION_PROMPT = """Extract facts from text into structured format with FIVE required dimensions - BE EXTREMELY DETAILED.
+
+LANGUAGE REQUIREMENT: Detect the language of the input text. All extracted facts, entity names, descriptions,
+and other output MUST be in the SAME language as the input. Do not translate to English if the input is in another language.
+
+{fact_types_instruction}
 
 ══════════════════════════════════════════════════════════════════════════
 FACT FORMAT - ALL FIVE DIMENSIONS REQUIRED - MAXIMUM VERBOSITY
@@ -435,106 +640,88 @@ FACT TYPE
   Include: what the user asked, what problem they wanted solved, what context they provided
 
 ══════════════════════════════════════════════════════════════════════════
-USER PREFERENCES (CRITICAL)
+ENTITIES - EXTRACT EVERYTHING
 ══════════════════════════════════════════════════════════════════════════
 
-ALWAYS extract user preferences as separate facts! Watch for these keywords:
-- "enjoy", "like", "love", "prefer", "hate", "dislike", "favorite", "ideal", "dream", "want"
+Extract ALL of the following from the fact:
+- People names (Emily, Alice, Dr. Smith)
+- Organizations (Google, MIT, local coffee shop)
+- Places (San Francisco, Brooklyn, Paris)
+- Significant objects mentioned (coffee maker, new car, wedding dress)
+- Abstract concepts/themes (friendship, career growth, loss, celebration)
 
-Example: "I love Italian food and prefer outdoor dining"
-→ Fact 1: what="User loves Italian food", who="user", why="This is a food preference", entities=["user"]
-→ Fact 2: what="User prefers outdoor dining", who="user", why="This is a dining preference", entities=["user"]
+ALWAYS include "user" when fact is about the user.
+Extract anything that could help link related facts together."""
+
+
+# Causal relationships section - appended when causal extraction is enabled
+CAUSAL_RELATIONSHIPS_SECTION = """
 
 ══════════════════════════════════════════════════════════════════════════
-ENTITIES - INCLUDE PEOPLE, PLACES, OBJECTS, AND CONCEPTS (CRITICAL)
+CAUSAL RELATIONSHIPS
 ══════════════════════════════════════════════════════════════════════════
 
-Extract entities that help link related facts together. Include:
-1. "user" - when the fact is about the user
-2. People names - Emily, Dr. Smith, etc.
-3. Organizations/Places - IKEA, Goodwill, New York, etc.
-4. Specific objects - coffee maker, toaster, car, laptop, kitchen, etc.
-5. Abstract concepts - themes, values, emotions, or ideas that capture the essence of the fact:
-   - "friendship" for facts about friends helping each other, bonding, loyalty
-   - "career growth" for facts about promotions, learning new skills, job changes
-   - "loss" or "grief" for facts about death, endings, saying goodbye
-   - "celebration" for facts about parties, achievements, milestones
-   - "trust" or "betrayal" for facts involving those themes
+Link facts with causal_relations (max 2 per fact). target_index must be < this fact's index.
+Types: "caused_by", "enabled_by", "prevented_by"
 
-✅ CORRECT: entities=["user", "coffee maker", "Goodwill", "kitchen"] for "User donated their coffee maker to Goodwill"
-✅ CORRECT: entities=["user", "Emily", "friendship"] for "Emily helped user move to a new apartment"
-✅ CORRECT: entities=["user", "promotion", "career growth"] for "User got promoted to senior engineer"
-✅ CORRECT: entities=["user", "grandmother", "loss", "grief"] for "User's grandmother passed away last week"
-❌ WRONG: entities=["user", "Emily"] only - missing the "friendship" concept that links to other friendship facts!
+Example: "Lost job → couldn't pay rent → moved apartment"
+- Fact 0: Lost job, causal_relations: null
+- Fact 1: Couldn't pay rent, causal_relations: [{target_index: 0, relation_type: "caused_by"}]
+- Fact 2: Moved apartment, causal_relations: [{target_index: 1, relation_type: "caused_by"}]"""
 
-══════════════════════════════════════════════════════════════════════════
-EXAMPLES
-══════════════════════════════════════════════════════════════════════════
 
-Example 1 - World Facts (Event Date: Tuesday, June 10, 2024):
-Input: "I'm planning my wedding and want a small outdoor ceremony. I just got back from my college roommate Emily's wedding - she married Sarah at a rooftop garden, it was so romantic!"
+async def _extract_facts_from_chunk(
+    chunk: str,
+    chunk_index: int,
+    total_chunks: int,
+    event_date: datetime,
+    context: str,
+    llm_config: "LLMConfig",
+    agent_name: str = None,
+    extract_opinions: bool = False,
+) -> tuple[list[dict[str, str]], TokenUsage]:
+    """
+    Extract facts from a single chunk (internal helper for parallel processing).
 
-Output facts:
+    Note: event_date parameter is kept for backward compatibility but not used in prompt.
+    The LLM extracts temporal information from the context string instead.
+    """
+    memory_bank_context = f"\n- Your name: {agent_name}" if agent_name and extract_opinions else ""
 
-1. User's wedding preference
-   - what: "User wants a small outdoor ceremony for their wedding"
-   - who: "user"
-   - why: "User prefers intimate outdoor settings"
-   - fact_type: "world", fact_kind: "conversation"
-   - entities: ["user", "wedding", "outdoor ceremony"]
+    # Determine which fact types to extract based on the flag
+    # Note: We use "assistant" in the prompt but convert to "bank" for storage
+    if extract_opinions:
+        # Opinion extraction uses a separate prompt (not this one)
+        fact_types_instruction = "Extract ONLY 'opinion' type facts (formed opinions, beliefs, and perspectives). DO NOT extract 'world' or 'assistant' facts."
+    else:
+        fact_types_instruction = (
+            "Extract ONLY 'world' and 'assistant' type facts. DO NOT extract opinions - those are extracted separately."
+        )
 
-2. User planning wedding
-   - what: "User is planning their own wedding"
-   - who: "user"
-   - why: "Inspired by Emily's ceremony"
-   - fact_type: "world", fact_kind: "conversation"
-   - entities: ["user", "wedding"]
+    # Check config for extraction mode and causal link extraction
+    config = get_config()
+    extraction_mode = config.retain_extraction_mode
+    extract_causal_links = config.retain_extract_causal_links
 
-3. Emily's wedding (THE EVENT - note occurred_start AND occurred_end both set)
-   - what: "Emily got married to Sarah at a rooftop garden ceremony in the city"
-   - who: "Emily (user's college roommate), Sarah (Emily's partner)"
-   - why: "User found it romantic and beautiful"
-   - fact_type: "world", fact_kind: "event"
-   - occurred_start: "2024-06-09T00:00:00Z" (recently, user "just got back" - relative to Event Date June 10, 2024)
-   - occurred_end: "2024-06-09T23:59:59Z" (same day - point event)
-   - entities: ["user", "Emily", "Sarah", "wedding", "rooftop garden"]
+    # Select base prompt based on extraction mode
+    if extraction_mode == "verbose":
+        base_prompt = VERBOSE_FACT_EXTRACTION_PROMPT
+    else:
+        base_prompt = CONCISE_FACT_EXTRACTION_PROMPT
 
-Example 2 - Assistant Facts (Context: March 5, 2024):
-Input: "User: My API is really slow when we have 1000+ concurrent users. What can I do?
-Assistant: I'd recommend implementing Redis for caching frequently-accessed data, which should reduce your database load by 70-80%."
+    # Format the prompt with fact types instruction
+    prompt = base_prompt.format(fact_types_instruction=fact_types_instruction)
 
-Output fact:
-   - what: "Assistant recommended implementing Redis for caching frequently-accessed data to improve API performance"
-   - when: "March 5, 2024 during conversation"
-   - who: "user, assistant"
-   - why: "User asked how to fix slow API performance with 1000+ concurrent users, expected 70-80% reduction in database load"
-   - fact_type: "assistant", fact_kind: "conversation"
-   - entities: ["user", "API", "Redis"]
-
-Example 3 - Kitchen Items with Concept Inference (Event Date: Thursday, May 30, 2024):
-Input: "I finally donated my old coffee maker to Goodwill. I upgraded to that new espresso machine last month and the old one was just taking up counter space."
-
-Output fact:
-   - what: "User donated their old coffee maker to Goodwill after upgrading to a new espresso machine"
-   - when: "Thursday, May 30, 2024"
-   - who: "user"
-   - why: "The old coffee maker was taking up counter space after the upgrade"
-   - fact_type: "world", fact_kind: "event"
-   - occurred_start: "2024-05-30T00:00:00Z" (uses Event Date year)
-   - occurred_end: "2024-05-30T23:59:59Z" (same day - point event)
-   - entities: ["user", "coffee maker", "Goodwill", "espresso machine", "kitchen"]
-
-Note: "kitchen" is inferred as a concept because coffee makers and espresso machines are kitchen appliances.
-This links the fact to other kitchen-related facts (toaster, faucet, kitchen mat, etc.) via the shared "kitchen" entity.
-
-Note how the "why" field captures the FULL STORY: what the user asked AND what outcome was expected!
-
-══════════════════════════════════════════════════════════════════════════
-WHAT TO EXTRACT vs SKIP
-══════════════════════════════════════════════════════════════════════════
-
-✅ EXTRACT: User preferences (ALWAYS as separate facts!), feelings, plans, events, relationships, achievements
-❌ SKIP: Greetings, filler ("thanks", "cool"), purely structural statements"""
+    # Build the full prompt with or without causal relationships section
+    # Select appropriate response schema based on extraction mode and causal links
+    if extract_causal_links:
+        prompt = prompt + CAUSAL_RELATIONSHIPS_SECTION
+        if extraction_mode == "verbose":
+            response_schema = FactExtractionResponseVerbose
+        else:
+            response_schema = FactExtractionResponse
+    else:
+        response_schema = FactExtractionResponseNoCausal
 
     import logging
 
@@ -563,16 +750,19 @@ Context: {sanitized_context}
 Text:
 {sanitized_chunk}"""
 
+    usage = TokenUsage()  # Track cumulative usage across retries
     for attempt in range(max_retries):
         try:
-            extraction_response_json = await llm_config.call(
+            extraction_response_json, call_usage = await llm_config.call(
                 messages=[{"role": "system", "content": prompt}, {"role": "user", "content": user_message}],
-                response_format=FactExtractionResponse,
+                response_format=response_schema,
                 scope="memory_extract_facts",
                 temperature=0.1,
-                max_completion_tokens=65000,
+                max_completion_tokens=config.retain_max_completion_tokens,
                 skip_validation=True,  # Get raw JSON, we'll validate leniently
+                return_usage=True,
             )
+            usage = usage + call_usage  # Aggregate usage across retries
 
             # Lenient parsing of facts from raw JSON
             chunk_facts = []
@@ -590,9 +780,10 @@ Text:
                         f"LLM returned non-dict JSON after {max_retries} attempts: {type(extraction_response_json).__name__}. "
                         f"Raw: {str(extraction_response_json)[:500]}"
                     )
-                    return []
+                    return [], usage
 
             raw_facts = extraction_response_json.get("facts", [])
+
             if not raw_facts:
                 logger.debug(
                     f"LLM response missing 'facts' field or returned empty list. "
@@ -676,13 +867,18 @@ Text:
                 if fact_kind == "event":
                     occurred_start = get_value("occurred_start")
                     occurred_end = get_value("occurred_end")
-                    if occurred_start:
+
+                    # If LLM didn't set temporal fields, try to extract them from the fact text
+                    if not occurred_start:
+                        fact_data["occurred_start"] = _infer_temporal_date(combined_text, event_date)
+                    else:
                         fact_data["occurred_start"] = occurred_start
-                        # For point events: if occurred_end not set, default to occurred_start
-                        if occurred_end:
-                            fact_data["occurred_end"] = occurred_end
-                        else:
-                            fact_data["occurred_end"] = occurred_start
+
+                    # For point events: if occurred_end not set, default to occurred_start
+                    if occurred_end:
+                        fact_data["occurred_end"] = occurred_end
+                    elif fact_data.get("occurred_start"):
+                        fact_data["occurred_end"] = fact_data["occurred_start"]
 
                 # Add entities if present (validate as Entity objects)
                 # LLM sometimes returns strings instead of {"text": "..."} format
@@ -702,17 +898,40 @@ Text:
                     if validated_entities:
                         fact_data["entities"] = validated_entities
 
-                # Add causal relations if present (validate as CausalRelation objects)
-                # Filter out invalid relations (missing required fields)
-                causal_relations = get_value("causal_relations")
-                if causal_relations:
+                # Add per-fact causal relations (only if enabled in config)
+                if extract_causal_links:
                     validated_relations = []
-                    for rel in causal_relations:
-                        if isinstance(rel, dict) and "target_fact_index" in rel and "relation_type" in rel:
+                    causal_relations_raw = get_value("causal_relations")
+                    if causal_relations_raw:
+                        for rel in causal_relations_raw:
+                            if not isinstance(rel, dict):
+                                continue
+                            # New schema uses target_index
+                            target_idx = rel.get("target_index")
+                            relation_type = rel.get("relation_type")
+                            strength = rel.get("strength", 1.0)
+
+                            if target_idx is None or relation_type is None:
+                                continue
+
+                            # Validate: target_index must be < current fact index
+                            if target_idx < 0 or target_idx >= i:
+                                logger.debug(
+                                    f"Invalid target_index {target_idx} for fact {i} (must be 0 to {i - 1}). Skipping."
+                                )
+                                continue
+
                             try:
-                                validated_relations.append(CausalRelation.model_validate(rel))
+                                validated_relations.append(
+                                    CausalRelation(
+                                        target_fact_index=target_idx,
+                                        relation_type=relation_type,
+                                        strength=strength,
+                                    )
+                                )
                             except Exception as e:
-                                logger.warning(f"Invalid causal relation {rel}: {e}")
+                                logger.debug(f"Invalid causal relation {rel}: {e}")
+
                     if validated_relations:
                         fact_data["causal_relations"] = validated_relations
 
@@ -735,7 +954,7 @@ Text:
                 )
                 continue
 
-            return chunk_facts
+            return chunk_facts, usage
 
         except BadRequestError as e:
             last_error = e
@@ -762,7 +981,7 @@ async def _extract_facts_with_auto_split(
     llm_config: LLMConfig,
     agent_name: str = None,
     extract_opinions: bool = False,
-) -> list[dict[str, str]]:
+) -> tuple[list[dict[str, str]], TokenUsage]:
     """
     Extract facts from a chunk with automatic splitting if output exceeds token limits.
 
@@ -780,7 +999,7 @@ async def _extract_facts_with_auto_split(
         extract_opinions: If True, extract ONLY opinions. If False, extract world and agent facts (no opinions)
 
     Returns:
-        List of fact dictionaries extracted from the chunk (possibly from sub-chunks)
+        Tuple of (facts list, token usage) extracted from the chunk (possibly from sub-chunks)
     """
     import logging
 
@@ -859,12 +1078,14 @@ async def _extract_facts_with_auto_split(
 
         # Combine results from both halves
         all_facts = []
-        for sub_result in sub_results:
-            all_facts.extend(sub_result)
+        total_usage = TokenUsage()
+        for sub_facts, sub_usage in sub_results:
+            all_facts.extend(sub_facts)
+            total_usage = total_usage + sub_usage
 
         logger.info(f"Successfully extracted {len(all_facts)} facts from split chunk {chunk_index + 1}")
 
-        return all_facts
+        return all_facts, total_usage
 
 
 async def extract_facts_from_text(
@@ -874,7 +1095,7 @@ async def extract_facts_from_text(
     agent_name: str,
     context: str = "",
     extract_opinions: bool = False,
-) -> tuple[list[Fact], list[tuple[str, int]]]:
+) -> tuple[list[Fact], list[tuple[str, int]], TokenUsage]:
     """
     Extract semantic facts from conversational or narrative text using LLM.
 
@@ -893,11 +1114,22 @@ async def extract_facts_from_text(
         extract_opinions: If True, extract ONLY opinions. If False, extract world and bank facts (no opinions)
 
     Returns:
-        Tuple of (facts, chunks) where:
+        Tuple of (facts, chunks, usage) where:
         - facts: List of Fact model instances
         - chunks: List of tuples (chunk_text, fact_count) for each chunk
+        - usage: Aggregated token usage across all LLM calls
     """
-    chunks = chunk_text(text, max_chars=3000)
+    config = get_config()
+    chunks = chunk_text(text, max_chars=config.retain_chunk_size)
+
+    # Log chunk count before starting LLM requests
+    total_chars = sum(len(c) for c in chunks)
+    if len(chunks) > 1:
+        logger.debug(
+            f"[FACT_EXTRACTION] Text chunked into {len(chunks)} chunks ({total_chars:,} chars total, "
+            f"chunk_size={config.retain_chunk_size:,}) - starting parallel LLM extraction"
+        )
+
     tasks = [
         _extract_facts_with_auto_split(
             chunk=chunk,
@@ -914,10 +1146,12 @@ async def extract_facts_from_text(
     chunk_results = await asyncio.gather(*tasks)
     all_facts = []
     chunk_metadata = []  # [(chunk_text, fact_count), ...]
-    for chunk, chunk_facts in zip(chunks, chunk_results):
+    total_usage = TokenUsage()
+    for chunk, (chunk_facts, chunk_usage) in zip(chunks, chunk_results):
         all_facts.extend(chunk_facts)
         chunk_metadata.append((chunk, len(chunk_facts)))
-    return all_facts, chunk_metadata
+        total_usage = total_usage + chunk_usage
+    return all_facts, chunk_metadata, total_usage
 
 
 # ============================================================================
@@ -938,7 +1172,7 @@ SECONDS_PER_FACT = 10
 
 async def extract_facts_from_contents(
     contents: list[RetainContent], llm_config, agent_name: str, extract_opinions: bool = False
-) -> tuple[list[ExtractedFactType], list[ChunkMetadata]]:
+) -> tuple[list[ExtractedFactType], list[ChunkMetadata], TokenUsage]:
     """
     Extract facts from multiple content items in parallel.
 
@@ -955,10 +1189,10 @@ async def extract_facts_from_contents(
         extract_opinions: If True, extract only opinions; otherwise world/bank facts
 
     Returns:
-        Tuple of (extracted_facts, chunks_metadata)
+        Tuple of (extracted_facts, chunks_metadata, usage)
     """
     if not contents:
-        return [], []
+        return [], [], TokenUsage()
 
     # Step 1: Create parallel fact extraction tasks
     fact_extraction_tasks = []
@@ -981,11 +1215,15 @@ async def extract_facts_from_contents(
     # Step 3: Flatten and convert to typed objects
     extracted_facts: list[ExtractedFactType] = []
     chunks_metadata: list[ChunkMetadata] = []
+    total_usage = TokenUsage()
 
     global_chunk_idx = 0
     global_fact_idx = 0
 
-    for content_index, (content, (facts_from_llm, chunks_from_llm)) in enumerate(zip(contents, all_fact_results)):
+    for content_index, (content, (facts_from_llm, chunks_from_llm, content_usage)) in enumerate(
+        zip(contents, all_fact_results)
+    ):
+        total_usage = total_usage + content_usage
         chunk_start_idx = global_chunk_idx
 
         # Convert chunk tuples to ChunkMetadata objects
@@ -1030,6 +1268,7 @@ async def extract_facts_from_contents(
                         # mentioned_at: always the event_date (when the conversation/document occurred)
                         mentioned_at=content.event_date,
                         metadata=content.metadata,
+                        tags=content.tags,
                     )
 
                     extracted_facts.append(extracted_fact)
@@ -1039,7 +1278,7 @@ async def extract_facts_from_contents(
     # Step 4: Add time offsets to preserve ordering within each content
     _add_temporal_offsets(extracted_facts, contents)
 
-    return extracted_facts, chunks_metadata
+    return extracted_facts, chunks_metadata, total_usage
 
 
 def _parse_datetime(date_str: str):

hindsight-api/hindsight_api/engine/retain/fact_storage.py

@@ -7,6 +7,7 @@ Handles insertion of facts into the database.
 import json
 import logging
 
+from ..memory_engine import fq_table
 from .types import ProcessedFact
 
 logger = logging.getLogger(__name__)
@@ -44,6 +45,7 @@ async def insert_facts_batch(
     metadata_jsons = []
     chunk_ids = []
     document_ids = []
+    tags_list = []
 
     for fact in facts:
         fact_texts.append(fact.fact_text)
@@ -64,16 +66,31 @@ async def insert_facts_batch(
         chunk_ids.append(fact.chunk_id)
         # Use per-fact document_id if available, otherwise fallback to batch-level document_id
         document_ids.append(fact.document_id if fact.document_id else document_id)
+        # Convert tags to JSON string for proper batch insertion (PostgreSQL unnest doesn't handle 2D arrays well)
+        tags_list.append(json.dumps(fact.tags if fact.tags else []))
 
     # Batch insert all facts
+    # Note: tags are passed as JSON strings and converted back to varchar[] via jsonb_array_elements_text + array_agg
     results = await conn.fetch(
-        """
-        INSERT INTO memory_units (bank_id, text, embedding, event_date, occurred_start, occurred_end, mentioned_at,
-                                 context, fact_type, confidence_score, access_count, metadata, chunk_id, document_id)
-        SELECT $1, * FROM unnest(
-            $2::text[], $3::vector[], $4::timestamptz[], $5::timestamptz[], $6::timestamptz[], $7::timestamptz[],
-            $8::text[], $9::text[], $10::float[], $11::int[], $12::jsonb[], $13::text[], $14::text[]
+        f"""
+        WITH input_data AS (
+            SELECT * FROM unnest(
+                $2::text[], $3::vector[], $4::timestamptz[], $5::timestamptz[], $6::timestamptz[], $7::timestamptz[],
+                $8::text[], $9::text[], $10::float[], $11::int[], $12::jsonb[], $13::text[], $14::text[], $15::jsonb[]
+            ) AS t(text, embedding, event_date, occurred_start, occurred_end, mentioned_at,
+                   context, fact_type, confidence_score, access_count, metadata, chunk_id, document_id, tags_json)
         )
+        INSERT INTO {fq_table("memory_units")} (bank_id, text, embedding, event_date, occurred_start, occurred_end, mentioned_at,
+                                 context, fact_type, confidence_score, access_count, metadata, chunk_id, document_id, tags)
+        SELECT
+            $1,
+            text, embedding, event_date, occurred_start, occurred_end, mentioned_at,
+            context, fact_type, confidence_score, access_count, metadata, chunk_id, document_id,
+            COALESCE(
+                (SELECT array_agg(elem) FROM jsonb_array_elements_text(tags_json) AS elem),
+                '{{}}'::varchar[]
+            )
+        FROM input_data
         RETURNING id
         """,
         bank_id,
@@ -90,6 +107,7 @@ async def insert_facts_batch(
         metadata_jsons,
         chunk_ids,
         document_ids,
+        tags_list,
     )
 
     unit_ids = [str(row["id"]) for row in results]
@@ -107,8 +125,8 @@ async def ensure_bank_exists(conn, bank_id: str) -> None:
         bank_id: Bank identifier
     """
     await conn.execute(
-        """
-        INSERT INTO banks (bank_id, disposition, background)
+        f"""
+        INSERT INTO {fq_table("banks")} (bank_id, disposition, mission)
         VALUES ($1, $2::jsonb, $3)
         ON CONFLICT (bank_id) DO UPDATE
         SET updated_at = NOW()
@@ -120,7 +138,13 @@ async def ensure_bank_exists(conn, bank_id: str) -> None:
 
 
 async def handle_document_tracking(
-    conn, bank_id: str, document_id: str, combined_content: str, is_first_batch: bool, retain_params: dict | None = None
+    conn,
+    bank_id: str,
+    document_id: str,
+    combined_content: str,
+    is_first_batch: bool,
+    retain_params: dict | None = None,
+    document_tags: list[str] | None = None,
 ) -> None:
     """
     Handle document tracking in the database.
@@ -132,6 +156,7 @@ async def handle_document_tracking(
         combined_content: Combined content text from all content items
         is_first_batch: Whether this is the first batch (for chunked operations)
         retain_params: Optional parameters passed during retain (context, event_date, etc.)
+        document_tags: Optional list of tags to associate with the document
     """
     import hashlib
 
@@ -141,18 +166,21 @@ async def handle_document_tracking(
     # Always delete old document first if it exists (cascades to units and links)
     # Only delete on the first batch to avoid deleting data we just inserted
     if is_first_batch:
-        await conn.fetchval("DELETE FROM documents WHERE id = $1 AND bank_id = $2 RETURNING id", document_id, bank_id)
+        await conn.fetchval(
+            f"DELETE FROM {fq_table('documents')} WHERE id = $1 AND bank_id = $2 RETURNING id", document_id, bank_id
+        )
 
     # Insert document (or update if exists from concurrent operations)
     await conn.execute(
-        """
-        INSERT INTO documents (id, bank_id, original_text, content_hash, metadata, retain_params)
-        VALUES ($1, $2, $3, $4, $5, $6)
+        f"""
+        INSERT INTO {fq_table("documents")} (id, bank_id, original_text, content_hash, metadata, retain_params, tags)
+        VALUES ($1, $2, $3, $4, $5, $6, $7)
         ON CONFLICT (id, bank_id) DO UPDATE
         SET original_text = EXCLUDED.original_text,
             content_hash = EXCLUDED.content_hash,
             metadata = EXCLUDED.metadata,
             retain_params = EXCLUDED.retain_params,
+            tags = EXCLUDED.tags,
             updated_at = NOW()
         """,
         document_id,
@@ -161,4 +189,5 @@ async def handle_document_tracking(
         content_hash,
         json.dumps({}),  # Empty metadata dict
         json.dumps(retain_params) if retain_params else None,
+        document_tags or [],
     )

hindsight-api/hindsight_api/engine/retain/link_utils.py

@@ -7,6 +7,7 @@ import time
 from datetime import UTC, datetime, timedelta
 from uuid import UUID
 
+from ..memory_engine import fq_table
 from .types import EntityLink
 
 logger = logging.getLogger(__name__)
@@ -290,9 +291,9 @@ async def extract_entities_batch_optimized(
 
             entity_id_list = [uuid.UUID(eid) if isinstance(eid, str) else eid for eid in all_entity_ids]
             rows = await conn.fetch(
-                """
+                f"""
                 SELECT entity_id, unit_id
-                FROM unit_entities
+                FROM {fq_table("unit_entities")}
                 WHERE entity_id = ANY($1::uuid[])
                 """,
                 entity_id_list,
@@ -413,9 +414,9 @@ async def create_temporal_links_batch_per_fact(
         # Get the event_date for each new unit
         fetch_dates_start = time_mod.time()
         rows = await conn.fetch(
-            """
+            f"""
             SELECT id, event_date
-            FROM memory_units
+            FROM {fq_table("memory_units")}
             WHERE id::text = ANY($1)
             """,
             unit_ids,
@@ -432,9 +433,9 @@ async def create_temporal_links_batch_per_fact(
 
         fetch_neighbors_start = time_mod.time()
         all_candidates = await conn.fetch(
-            """
+            f"""
             SELECT id, event_date
-            FROM memory_units
+            FROM {fq_table("memory_units")}
             WHERE bank_id = $1
               AND event_date BETWEEN $2 AND $3
               AND id::text != ALL($4)
@@ -478,14 +479,18 @@ async def create_temporal_links_batch_per_fact(
 
         if links:
             insert_start = time_mod.time()
-            await conn.executemany(
-                """
-                INSERT INTO memory_links (from_unit_id, to_unit_id, link_type, weight, entity_id)
-                VALUES ($1, $2, $3, $4, $5)
-                ON CONFLICT (from_unit_id, to_unit_id, link_type, COALESCE(entity_id, '00000000-0000-0000-0000-000000000000'::uuid)) DO NOTHING
-                """,
-                links,
-            )
+            # Batch inserts to avoid timeout on large batches
+            BATCH_SIZE = 1000
+            for batch_start in range(0, len(links), BATCH_SIZE):
+                batch = links[batch_start : batch_start + BATCH_SIZE]
+                await conn.executemany(
+                    f"""
+                    INSERT INTO {fq_table("memory_links")} (from_unit_id, to_unit_id, link_type, weight, entity_id)
+                    VALUES ($1, $2, $3, $4, $5)
+                    ON CONFLICT (from_unit_id, to_unit_id, link_type, COALESCE(entity_id, '00000000-0000-0000-0000-000000000000'::uuid)) DO NOTHING
+                    """,
+                    batch,
+                )
             _log(log_buffer, f"      [7.4] Insert {len(links)} temporal links: {time_mod.time() - insert_start:.3f}s")
 
         return len(links)
@@ -535,9 +540,9 @@ async def create_semantic_links_batch(
         # Fetch ALL existing units with embeddings in ONE query
         fetch_start = time_mod.time()
         all_existing = await conn.fetch(
-            """
+            f"""
             SELECT id, embedding
-            FROM memory_units
+            FROM {fq_table("memory_units")}
             WHERE bank_id = $1
               AND embedding IS NOT NULL
               AND id::text != ALL($2)
@@ -643,14 +648,18 @@ async def create_semantic_links_batch(
 
         if all_links:
             insert_start = time_mod.time()
-            await conn.executemany(
-                """
-                INSERT INTO memory_links (from_unit_id, to_unit_id, link_type, weight, entity_id)
-                VALUES ($1, $2, $3, $4, $5)
-                ON CONFLICT (from_unit_id, to_unit_id, link_type, COALESCE(entity_id, '00000000-0000-0000-0000-000000000000'::uuid)) DO NOTHING
-                """,
-                all_links,
-            )
+            # Batch inserts to avoid timeout on large batches
+            BATCH_SIZE = 1000
+            for batch_start in range(0, len(all_links), BATCH_SIZE):
+                batch = all_links[batch_start : batch_start + BATCH_SIZE]
+                await conn.executemany(
+                    f"""
+                    INSERT INTO {fq_table("memory_links")} (from_unit_id, to_unit_id, link_type, weight, entity_id)
+                    VALUES ($1, $2, $3, $4, $5)
+                    ON CONFLICT (from_unit_id, to_unit_id, link_type, COALESCE(entity_id, '00000000-0000-0000-0000-000000000000'::uuid)) DO NOTHING
+                    """,
+                    batch,
+                )
             _log(
                 log_buffer, f"      [8.3] Insert {len(all_links)} semantic links: {time_mod.time() - insert_start:.3f}s"
             )
@@ -721,8 +730,8 @@ async def insert_entity_links_batch(conn, links: list[EntityLink], chunk_size: i
 
     # Insert from temp table with ON CONFLICT (single query for all rows)
     insert_start = time_mod.time()
-    await conn.execute("""
-        INSERT INTO memory_links (from_unit_id, to_unit_id, link_type, weight, entity_id)
+    await conn.execute(f"""
+        INSERT INTO {fq_table("memory_links")} (from_unit_id, to_unit_id, link_type, weight, entity_id)
         SELECT from_unit_id, to_unit_id, link_type, weight, entity_id
         FROM _temp_entity_links
         ON CONFLICT (from_unit_id, to_unit_id, link_type, COALESCE(entity_id, '00000000-0000-0000-0000-000000000000'::uuid)) DO NOTHING
@@ -808,8 +817,8 @@ async def create_causal_links_batch(
             insert_start = time_mod.time()
             try:
                 await conn.executemany(
-                    """
-                    INSERT INTO memory_links (from_unit_id, to_unit_id, link_type, weight, entity_id)
+                    f"""
+                    INSERT INTO {fq_table("memory_links")} (from_unit_id, to_unit_id, link_type, weight, entity_id)
                     VALUES ($1, $2, $3, $4, $5)
                     ON CONFLICT (from_unit_id, to_unit_id, link_type, COALESCE(entity_id, '00000000-0000-0000-0000-000000000000'::uuid)) DO NOTHING
                     """,

hindsight-api/hindsight_api/engine/retain/observation_regeneration.py

@@ -1,251 +0,0 @@
-"""
-Observation regeneration for retain pipeline.
-
-Regenerates entity observations as part of the retain transaction.
-"""
-
-import logging
-import time
-import uuid
-from datetime import UTC, datetime
-
-from ..search import observation_utils
-from . import embedding_utils
-from .types import EntityLink
-
-logger = logging.getLogger(__name__)
-
-
-def utcnow():
-    """Get current UTC time."""
-    return datetime.now(UTC)
-
-
-# Simple dataclass-like container for facts (avoid importing from memory_engine)
-class MemoryFactForObservation:
-    def __init__(self, id: str, text: str, fact_type: str, context: str, occurred_start: str | None):
-        self.id = id
-        self.text = text
-        self.fact_type = fact_type
-        self.context = context
-        self.occurred_start = occurred_start
-
-
-async def regenerate_observations_batch(
-    conn, embeddings_model, llm_config, bank_id: str, entity_links: list[EntityLink], log_buffer: list[str] = None
-) -> None:
-    """
-    Regenerate observations for top entities in this batch.
-
-    Called INSIDE the retain transaction for atomicity - if observations
-    fail, the entire retain batch is rolled back.
-
-    Args:
-        conn: Database connection (from the retain transaction)
-        embeddings_model: Embeddings model for generating observation embeddings
-        llm_config: LLM configuration for observation extraction
-        bank_id: Bank identifier
-        entity_links: Entity links from this batch
-        log_buffer: Optional log buffer for timing
-    """
-    TOP_N_ENTITIES = 5
-    MIN_FACTS_THRESHOLD = 5
-
-    if not entity_links:
-        return
-
-    # Count mentions per entity in this batch
-    entity_mention_counts: dict[str, int] = {}
-    for link in entity_links:
-        if link.entity_id:
-            entity_id = str(link.entity_id)
-            entity_mention_counts[entity_id] = entity_mention_counts.get(entity_id, 0) + 1
-
-    if not entity_mention_counts:
-        return
-
-    # Sort by mention count descending and take top N
-    sorted_entities = sorted(entity_mention_counts.items(), key=lambda x: x[1], reverse=True)
-    entities_to_process = [e[0] for e in sorted_entities[:TOP_N_ENTITIES]]
-
-    obs_start = time.time()
-
-    # Convert to UUIDs
-    entity_uuids = [uuid.UUID(eid) if isinstance(eid, str) else eid for eid in entities_to_process]
-
-    # Batch query for entity names
-    entity_rows = await conn.fetch(
-        """
-        SELECT id, canonical_name FROM entities
-        WHERE id = ANY($1) AND bank_id = $2
-        """,
-        entity_uuids,
-        bank_id,
-    )
-    entity_names = {row["id"]: row["canonical_name"] for row in entity_rows}
-
-    # Batch query for fact counts
-    fact_counts = await conn.fetch(
-        """
-        SELECT ue.entity_id, COUNT(*) as cnt
-        FROM unit_entities ue
-        JOIN memory_units mu ON ue.unit_id = mu.id
-        WHERE ue.entity_id = ANY($1) AND mu.bank_id = $2
-        GROUP BY ue.entity_id
-        """,
-        entity_uuids,
-        bank_id,
-    )
-    entity_fact_counts = {row["entity_id"]: row["cnt"] for row in fact_counts}
-
-    # Filter entities that meet the threshold
-    entities_with_names = []
-    for entity_id in entities_to_process:
-        entity_uuid = uuid.UUID(entity_id) if isinstance(entity_id, str) else entity_id
-        if entity_uuid not in entity_names:
-            continue
-        fact_count = entity_fact_counts.get(entity_uuid, 0)
-        if fact_count >= MIN_FACTS_THRESHOLD:
-            entities_with_names.append((entity_id, entity_names[entity_uuid]))
-
-    if not entities_with_names:
-        return
-
-    # Process entities SEQUENTIALLY (asyncpg doesn't allow concurrent queries on same connection)
-    # We must use the same connection to stay in the retain transaction
-    total_observations = 0
-
-    for entity_id, entity_name in entities_with_names:
-        try:
-            obs_ids = await _regenerate_entity_observations(
-                conn, embeddings_model, llm_config, bank_id, entity_id, entity_name
-            )
-            total_observations += len(obs_ids)
-        except Exception as e:
-            logger.error(f"[OBSERVATIONS] Error processing entity {entity_id}: {e}")
-
-    obs_time = time.time() - obs_start
-    if log_buffer is not None:
-        log_buffer.append(
-            f"[11] Observations: {total_observations} observations for {len(entities_with_names)} entities in {obs_time:.3f}s"
-        )
-
-
-async def _regenerate_entity_observations(
-    conn, embeddings_model, llm_config, bank_id: str, entity_id: str, entity_name: str
-) -> list[str]:
-    """
-    Regenerate observations for a single entity.
-
-    Uses the provided connection (part of retain transaction).
-
-    Args:
-        conn: Database connection (from the retain transaction)
-        embeddings_model: Embeddings model
-        llm_config: LLM configuration
-        bank_id: Bank identifier
-        entity_id: Entity UUID
-        entity_name: Canonical name of the entity
-
-    Returns:
-        List of created observation IDs
-    """
-    entity_uuid = uuid.UUID(entity_id) if isinstance(entity_id, str) else entity_id
-
-    # Get all facts mentioning this entity (exclude observations themselves)
-    rows = await conn.fetch(
-        """
-        SELECT mu.id, mu.text, mu.context, mu.occurred_start, mu.fact_type
-        FROM memory_units mu
-        JOIN unit_entities ue ON mu.id = ue.unit_id
-        WHERE mu.bank_id = $1
-          AND ue.entity_id = $2
-          AND mu.fact_type IN ('world', 'experience')
-        ORDER BY mu.occurred_start DESC
-        LIMIT 50
-        """,
-        bank_id,
-        entity_uuid,
-    )
-
-    if not rows:
-        return []
-
-    # Convert to fact objects for observation extraction
-    facts = []
-    for row in rows:
-        occurred_start = row["occurred_start"].isoformat() if row["occurred_start"] else None
-        facts.append(
-            MemoryFactForObservation(
-                id=str(row["id"]),
-                text=row["text"],
-                fact_type=row["fact_type"],
-                context=row["context"],
-                occurred_start=occurred_start,
-            )
-        )
-
-    # Extract observations using LLM
-    observations = await observation_utils.extract_observations_from_facts(llm_config, entity_name, facts)
-
-    if not observations:
-        return []
-
-    # Delete old observations for this entity
-    await conn.execute(
-        """
-        DELETE FROM memory_units
-        WHERE id IN (
-            SELECT mu.id
-            FROM memory_units mu
-            JOIN unit_entities ue ON mu.id = ue.unit_id
-            WHERE mu.bank_id = $1
-              AND mu.fact_type = 'observation'
-              AND ue.entity_id = $2
-        )
-        """,
-        bank_id,
-        entity_uuid,
-    )
-
-    # Generate embeddings for new observations
-    embeddings = await embedding_utils.generate_embeddings_batch(embeddings_model, observations)
-
-    # Insert new observations
-    current_time = utcnow()
-    created_ids = []
-
-    for obs_text, embedding in zip(observations, embeddings):
-        result = await conn.fetchrow(
-            """
-            INSERT INTO memory_units (
-                bank_id, text, embedding, context, event_date,
-                occurred_start, occurred_end, mentioned_at,
-                fact_type, access_count
-            )
-            VALUES ($1, $2, $3, $4, $5, $6, $7, $8, 'observation', 0)
-            RETURNING id
-            """,
-            bank_id,
-            obs_text,
-            str(embedding),
-            f"observation about {entity_name}",
-            current_time,
-            current_time,
-            current_time,
-            current_time,
-        )
-        obs_id = str(result["id"])
-        created_ids.append(obs_id)
-
-        # Link observation to entity
-        await conn.execute(
-            """
-            INSERT INTO unit_entities (unit_id, entity_id)
-            VALUES ($1, $2)
-            """,
-            uuid.UUID(obs_id),
-            entity_uuid,
-        )
-
-    return created_ids

hindsight-api/hindsight_api/engine/retain/orchestrator.py

@@ -8,7 +8,6 @@ import logging
 import time
 import uuid
 from datetime import UTC, datetime
-from typing import Any
 
 from ..db_utils import acquire_with_retry
 from . import bank_utils
@@ -19,6 +18,7 @@ def utcnow():
     return datetime.now(UTC)
 
 
+from ..response_models import TokenUsage
 from . import (
     chunk_storage,
     deduplication,
@@ -27,9 +27,8 @@ from . import (
     fact_extraction,
     fact_storage,
     link_creation,
-    observation_regeneration,
 )
-from .types import ExtractedFact, ProcessedFact, RetainContent
+from .types import EntityLink, ExtractedFact, ProcessedFact, RetainContent, RetainContentDict
 
 logger = logging.getLogger(__name__)
 
@@ -39,16 +38,16 @@ async def retain_batch(
     embeddings_model,
     llm_config,
     entity_resolver,
-    task_backend,
     format_date_fn,
     duplicate_checker_fn,
     bank_id: str,
-    contents_dicts: list[dict[str, Any]],
+    contents_dicts: list[RetainContentDict],
     document_id: str | None = None,
     is_first_batch: bool = True,
     fact_type_override: str | None = None,
     confidence_score: float | None = None,
-) -> list[list[str]]:
+    document_tags: list[str] | None = None,
+) -> tuple[list[list[str]], TokenUsage]:
     """
     Process a batch of content through the retain pipeline.
 
@@ -57,7 +56,6 @@ async def retain_batch(
         embeddings_model: Embeddings model for generating embeddings
         llm_config: LLM configuration for fact extraction
         entity_resolver: Entity resolver for entity processing
-        task_backend: Task backend for background jobs
         format_date_fn: Function to format datetime to readable string
         duplicate_checker_fn: Function to check for duplicate facts
         bank_id: Bank identifier
@@ -66,9 +64,10 @@ async def retain_batch(
         is_first_batch: Whether this is the first batch
         fact_type_override: Override fact type for all facts
         confidence_score: Confidence score for opinions
+        document_tags: Tags applied to all items in this batch
 
     Returns:
-        List of unit ID lists (one list per content item)
+        Tuple of (unit ID lists, token usage for fact extraction)
     """
     start_time = time.time()
     total_chars = sum(len(item.get("content", "")) for item in contents_dicts)
@@ -87,11 +86,16 @@ async def retain_batch(
     # Convert dicts to RetainContent objects
     contents = []
     for item in contents_dicts:
+        # Merge item-level tags with document-level tags
+        item_tags = item.get("tags", []) or []
+        merged_tags = list(set(item_tags + (document_tags or [])))
         content = RetainContent(
             content=item["content"],
             context=item.get("context", ""),
             event_date=item.get("event_date") or utcnow(),
             metadata=item.get("metadata", {}),
+            entities=item.get("entities", []),
+            tags=merged_tags,
         )
         contents.append(content)
 
@@ -99,7 +103,7 @@ async def retain_batch(
     step_start = time.time()
     extract_opinions = fact_type_override == "opinion"
 
-    extracted_facts, chunks = await fact_extraction.extract_facts_from_contents(
+    extracted_facts, chunks, usage = await fact_extraction.extract_facts_from_contents(
         contents, llm_config, agent_name, extract_opinions
     )
     log_buffer.append(
@@ -107,11 +111,64 @@ async def retain_batch(
     )
 
     if not extracted_facts:
+        # Still need to create document if document_id was provided
+        async with acquire_with_retry(pool) as conn:
+            async with conn.transaction():
+                await fact_storage.ensure_bank_exists(conn, bank_id)
+
+                # Handle document tracking even with no facts
+                if document_id:
+                    combined_content = "\n".join([c.get("content", "") for c in contents_dicts])
+                    retain_params = {}
+                    if contents_dicts:
+                        first_item = contents_dicts[0]
+                        if first_item.get("context"):
+                            retain_params["context"] = first_item["context"]
+                        if first_item.get("event_date"):
+                            retain_params["event_date"] = (
+                                first_item["event_date"].isoformat()
+                                if hasattr(first_item["event_date"], "isoformat")
+                                else str(first_item["event_date"])
+                            )
+                        if first_item.get("metadata"):
+                            retain_params["metadata"] = first_item["metadata"]
+                    await fact_storage.handle_document_tracking(
+                        conn, bank_id, document_id, combined_content, is_first_batch, retain_params, document_tags
+                    )
+                else:
+                    # Check for per-item document_ids
+                    from collections import defaultdict
+
+                    contents_by_doc = defaultdict(list)
+                    for idx, content_dict in enumerate(contents_dicts):
+                        doc_id = content_dict.get("document_id")
+                        if doc_id:
+                            contents_by_doc[doc_id].append((idx, content_dict))
+
+                    for doc_id, doc_contents in contents_by_doc.items():
+                        combined_content = "\n".join([c.get("content", "") for _, c in doc_contents])
+                        retain_params = {}
+                        if doc_contents:
+                            first_item = doc_contents[0][1]
+                            if first_item.get("context"):
+                                retain_params["context"] = first_item["context"]
+                            if first_item.get("event_date"):
+                                retain_params["event_date"] = (
+                                    first_item["event_date"].isoformat()
+                                    if hasattr(first_item["event_date"], "isoformat")
+                                    else str(first_item["event_date"])
+                                )
+                            if first_item.get("metadata"):
+                                retain_params["metadata"] = first_item["metadata"]
+                        await fact_storage.handle_document_tracking(
+                            conn, bank_id, doc_id, combined_content, is_first_batch, retain_params, document_tags
+                        )
+
         total_time = time.time() - start_time
         logger.info(
-            f"RETAIN_BATCH COMPLETE: 0 facts extracted from {len(contents)} contents in {total_time:.3f}s (nothing to store)"
+            f"RETAIN_BATCH COMPLETE: 0 facts extracted from {len(contents)} contents in {total_time:.3f}s (document tracked, no facts)"
         )
-        return [[] for _ in contents]
+        return [[] for _ in contents], usage
 
     # Apply fact_type_override if provided
     if fact_type_override:
@@ -170,7 +227,7 @@ async def retain_batch(
                         retain_params["metadata"] = first_item["metadata"]
 
                 await fact_storage.handle_document_tracking(
-                    conn, bank_id, document_id, combined_content, is_first_batch, retain_params
+                    conn, bank_id, document_id, combined_content, is_first_batch, retain_params, document_tags
                 )
                 document_ids_added.append(document_id)
                 doc_id_mapping[None] = document_id  # For backwards compatibility
@@ -214,7 +271,13 @@ async def retain_batch(
                                     retain_params["metadata"] = first_item["metadata"]
 
                             await fact_storage.handle_document_tracking(
-                                conn, bank_id, actual_doc_id, combined_content, is_first_batch, retain_params
+                                conn,
+                                bank_id,
+                                actual_doc_id,
+                                combined_content,
+                                is_first_batch,
+                                retain_params,
+                                document_tags,
                             )
                             document_ids_added.append(actual_doc_id)
 
@@ -291,7 +354,7 @@ async def retain_batch(
             non_duplicate_facts = deduplication.filter_duplicates(processed_facts, is_duplicate_flags)
 
             if not non_duplicate_facts:
-                return [[] for _ in contents]
+                return [[] for _ in contents], usage
 
             # Insert facts (document_id is now stored per-fact)
             step_start = time.time()
@@ -300,8 +363,18 @@ async def retain_batch(
 
             # Process entities
             step_start = time.time()
+            # Build map of content_index -> user entities for merging
+            user_entities_per_content = {
+                idx: content.entities for idx, content in enumerate(contents) if content.entities
+            }
             entity_links = await entity_processing.process_entities_batch(
-                entity_resolver, conn, bank_id, unit_ids, non_duplicate_facts, log_buffer
+                entity_resolver,
+                conn,
+                bank_id,
+                unit_ids,
+                non_duplicate_facts,
+                log_buffer,
+                user_entities_per_content=user_entities_per_content,
             )
             log_buffer.append(f"[6] Process entities: {len(entity_links)} links in {time.time() - step_start:.3f}s")
 
@@ -331,17 +404,9 @@ async def retain_batch(
             causal_link_count = await link_creation.create_causal_links_batch(conn, unit_ids, non_duplicate_facts)
             log_buffer.append(f"[10] Causal links: {causal_link_count} links in {time.time() - step_start:.3f}s")
 
-            # Regenerate observations INSIDE transaction for atomicity
-            await observation_regeneration.regenerate_observations_batch(
-                conn, embeddings_model, llm_config, bank_id, entity_links, log_buffer
-            )
-
             # Map results back to original content items
             result_unit_ids = _map_results_to_contents(contents, extracted_facts, is_duplicate_flags, unit_ids)
 
-        # Trigger background tasks AFTER transaction commits (opinion reinforcement only)
-        await _trigger_background_tasks(task_backend, bank_id, unit_ids, non_duplicate_facts)
-
         # Log final summary
         total_time = time.time() - start_time
         log_buffer.append(f"{'=' * 60}")
@@ -352,7 +417,7 @@ async def retain_batch(
 
         logger.info("\n" + "\n".join(log_buffer) + "\n")
 
-        return result_unit_ids
+        return result_unit_ids, usage
 
 
 def _map_results_to_contents(
@@ -383,24 +448,3 @@ def _map_results_to_contents(
         result_unit_ids.append(content_unit_ids)
 
     return result_unit_ids
-
-
-async def _trigger_background_tasks(
-    task_backend,
-    bank_id: str,
-    unit_ids: list[str],
-    facts: list[ProcessedFact],
-) -> None:
-    """Trigger opinion reinforcement as background task (after transaction commits)."""
-    # Trigger opinion reinforcement if there are entities
-    fact_entities = [[e.name for e in fact.entities] for fact in facts]
-    if any(fact_entities):
-        await task_backend.submit_task(
-            {
-                "type": "reinforce_opinion",
-                "bank_id": bank_id,
-                "created_unit_ids": unit_ids,
-                "unit_texts": [fact.fact_text for fact in facts],
-                "unit_entities": fact_entities,
-            }
-        )

hindsight-api/hindsight_api/engine/retain/types.py

@@ -7,9 +7,37 @@ from content input to fact storage.
 
 from dataclasses import dataclass, field
 from datetime import UTC, datetime
+from typing import TypedDict
 from uuid import UUID
 
 
+class RetainContentDict(TypedDict, total=False):
+    """Type definition for content items in retain_batch_async.
+
+    Fields:
+        content: Text content to store (required)
+        context: Context about the content (optional)
+        event_date: When the content occurred (optional, defaults to now)
+        metadata: Custom key-value metadata (optional)
+        document_id: Document ID for this content item (optional)
+        entities: User-provided entities to merge with extracted entities (optional)
+        tags: Visibility scope tags for this content item (optional)
+    """
+
+    content: str  # Required
+    context: str
+    event_date: datetime
+    metadata: dict[str, str]
+    document_id: str
+    entities: list[dict[str, str]]  # [{"text": "...", "type": "..."}]
+    tags: list[str]  # Visibility scope tags
+
+
+def _now_utc() -> datetime:
+    """Factory function for default event_date."""
+    return datetime.now(UTC)
+
+
 @dataclass
 class RetainContent:
     """
@@ -20,15 +48,10 @@ class RetainContent:
 
     content: str
     context: str = ""
-    event_date: datetime | None = None
+    event_date: datetime = field(default_factory=_now_utc)
     metadata: dict[str, str] = field(default_factory=dict)
-
-    def __post_init__(self):
-        """Ensure event_date is set."""
-        if self.event_date is None:
-            from datetime import datetime
-
-            self.event_date = datetime.now(UTC)
+    entities: list[dict[str, str]] = field(default_factory=list)  # User-provided entities
+    tags: list[str] = field(default_factory=list)  # Visibility scope tags
 
 
 @dataclass
@@ -93,6 +116,7 @@ class ExtractedFact:
     context: str = ""
     mentioned_at: datetime | None = None
     metadata: dict[str, str] = field(default_factory=dict)
+    tags: list[str] = field(default_factory=list)  # Visibility scope tags
 
 
 @dataclass
@@ -135,6 +159,12 @@ class ProcessedFact:
     # DB fields (set after insertion)
     unit_id: UUID | None = None
 
+    # Track which content this fact came from (for user entity merging)
+    content_index: int = 0
+
+    # Visibility scope tags
+    tags: list[str] = field(default_factory=list)
+
     @property
     def is_duplicate(self) -> bool:
         """Check if this fact was marked as a duplicate."""
@@ -177,6 +207,8 @@ class ProcessedFact:
             entities=entities,
             causal_relations=extracted_fact.causal_relations,
             chunk_id=chunk_id,
+            content_index=extracted_fact.content_index,
+            tags=extracted_fact.tags,
         )
 
 
@@ -208,6 +240,7 @@ class RetainBatch:
     document_id: str | None = None
     fact_type_override: str | None = None
     confidence_score: float | None = None
+    document_tags: list[str] = field(default_factory=list)  # Tags applied to all items
 
     # Extracted data (populated during processing)
     extracted_facts: list[ExtractedFact] = field(default_factory=list)

hindsight-api/hindsight_api/engine/search/graph_retrieval.py

@@ -10,7 +10,9 @@ import logging
 from abc import ABC, abstractmethod
 
 from ..db_utils import acquire_with_retry
-from .types import RetrievalResult
+from ..memory_engine import fq_table
+from .tags import TagsMatch, filter_results_by_tags
+from .types import MPFPTimings, RetrievalResult
 
 logger = logging.getLogger(__name__)
 
@@ -41,7 +43,10 @@ class GraphRetriever(ABC):
         query_text: str | None = None,
         semantic_seeds: list[RetrievalResult] | None = None,
         temporal_seeds: list[RetrievalResult] | None = None,
-    ) -> list[RetrievalResult]:
+        adjacency=None,  # TypedAdjacency, optional pre-loaded graph
+        tags: list[str] | None = None,  # Visibility scope tags for filtering
+        tags_match: TagsMatch = "any",  # How to match tags: 'any' (OR) or 'all' (AND)
+    ) -> tuple[list[RetrievalResult], MPFPTimings | None]:
         """
         Retrieve relevant facts via graph traversal.
 
@@ -54,9 +59,11 @@ class GraphRetriever(ABC):
             query_text: Original query text (optional, for some strategies)
             semantic_seeds: Pre-computed semantic entry points (from semantic retrieval)
             temporal_seeds: Pre-computed temporal entry points (from temporal retrieval)
+            adjacency: Pre-loaded typed adjacency graph (optional, for MPFP)
+            tags: Optional list of tags for visibility filtering (OR matching)
 
         Returns:
-            List of RetrievalResult objects with activation scores set
+            Tuple of (List of RetrievalResult with activation scores, optional timing info)
         """
         pass
 
@@ -110,7 +117,10 @@ class BFSGraphRetriever(GraphRetriever):
         query_text: str | None = None,
         semantic_seeds: list[RetrievalResult] | None = None,
         temporal_seeds: list[RetrievalResult] | None = None,
-    ) -> list[RetrievalResult]:
+        adjacency=None,  # Not used by BFS
+        tags: list[str] | None = None,
+        tags_match: TagsMatch = "any",
+    ) -> tuple[list[RetrievalResult], MPFPTimings | None]:
         """
         Retrieve facts using BFS spreading activation.
 
@@ -121,11 +131,14 @@ class BFSGraphRetriever(GraphRetriever):
         4. Return visited nodes up to budget
 
         Note: BFS finds its own entry points via embedding search.
-        The semantic_seeds and temporal_seeds parameters are accepted
+        The semantic_seeds, temporal_seeds, and adjacency parameters are accepted
         for interface compatibility but not used.
         """
         async with acquire_with_retry(pool) as conn:
-            return await self._retrieve_with_conn(conn, query_embedding_str, bank_id, fact_type, budget)
+            results = await self._retrieve_with_conn(
+                conn, query_embedding_str, bank_id, fact_type, budget, tags=tags, tags_match=tags_match
+            )
+            return results, None
 
     async def _retrieve_with_conn(
         self,
@@ -134,33 +147,46 @@ class BFSGraphRetriever(GraphRetriever):
         bank_id: str,
         fact_type: str,
         budget: int,
+        tags: list[str] | None = None,
+        tags_match: TagsMatch = "any",
     ) -> list[RetrievalResult]:
         """Internal implementation with connection."""
+        from .tags import build_tags_where_clause_simple
+
+        tags_clause = build_tags_where_clause_simple(tags, 6, match=tags_match)
+        params = [query_embedding_str, bank_id, fact_type, self.entry_point_threshold, self.entry_point_limit]
+        if tags:
+            params.append(tags)
 
         # Step 1: Find entry points
         entry_points = await conn.fetch(
-            """
+            f"""
             SELECT id, text, context, event_date, occurred_start, occurred_end,
-                   mentioned_at, access_count, embedding, fact_type, document_id, chunk_id,
+                   mentioned_at, access_count, embedding, fact_type, document_id, chunk_id, tags,
                    1 - (embedding <=> $1::vector) AS similarity
-            FROM memory_units
+            FROM {fq_table("memory_units")}
             WHERE bank_id = $2
               AND embedding IS NOT NULL
               AND fact_type = $3
               AND (1 - (embedding <=> $1::vector)) >= $4
+              {tags_clause}
             ORDER BY embedding <=> $1::vector
             LIMIT $5
             """,
-            query_embedding_str,
-            bank_id,
-            fact_type,
-            self.entry_point_threshold,
-            self.entry_point_limit,
+            *params,
         )
 
         if not entry_points:
+            logger.debug(
+                f"[BFS] No entry points found for fact_type={fact_type} (tags={tags}, tags_match={tags_match})"
+            )
             return []
 
+        logger.debug(
+            f"[BFS] Found {len(entry_points)} entry points for fact_type={fact_type} "
+            f"(tags={tags}, tags_match={tags_match})"
+        )
+
         # Step 2: BFS spreading activation
         visited = set()
         results = []
@@ -188,13 +214,13 @@ class BFSGraphRetriever(GraphRetriever):
             if batch_nodes and budget_remaining > 0:
                 max_neighbors = len(batch_nodes) * 20
                 neighbors = await conn.fetch(
-                    """
+                    f"""
                     SELECT mu.id, mu.text, mu.context, mu.occurred_start, mu.occurred_end,
                            mu.mentioned_at, mu.access_count, mu.embedding, mu.fact_type,
-                           mu.document_id, mu.chunk_id,
+                           mu.document_id, mu.chunk_id, mu.tags,
                            ml.weight, ml.link_type, ml.from_unit_id
-                    FROM memory_links ml
-                    JOIN memory_units mu ON ml.to_unit_id = mu.id
+                    FROM {fq_table("memory_links")} ml
+                    JOIN {fq_table("memory_units")} mu ON ml.to_unit_id = mu.id
                     WHERE ml.from_unit_id = ANY($1::uuid[])
                       AND ml.weight >= $2
                       AND mu.fact_type = $3
@@ -231,4 +257,8 @@ class BFSGraphRetriever(GraphRetriever):
                             neighbor_result = RetrievalResult.from_db_row(dict(n))
                             queue.append((neighbor_result, new_activation))
 
+        # Apply tags filtering (BFS may traverse into memories that don't match tags criteria)
+        if tags:
+            results = filter_results_by_tags(results, tags, match=tags_match)
+
         return results

hindsight-api/hindsight_api/engine/search/link_expansion_retrieval.py

@@ -0,0 +1,256 @@
+"""
+Link Expansion graph retrieval.
+
+A simple, fast graph retrieval that expands from seeds via:
+1. Entity links: Find facts sharing entities with seeds (filtered by entity frequency)
+2. Causal links: Find facts causally linked to seeds (top-k by weight)
+
+Characteristics:
+- 2-3 DB queries (seed finding + parallel entity/causal expansion)
+- Sublinear: only touches connected facts via indexes
+- No iteration, no propagation, no normalization
+- Target: <100ms
+"""
+
+import logging
+import time
+
+from ..db_utils import acquire_with_retry
+from ..memory_engine import fq_table
+from .graph_retrieval import GraphRetriever
+from .tags import TagsMatch, filter_results_by_tags
+from .types import MPFPTimings, RetrievalResult
+
+logger = logging.getLogger(__name__)
+
+
+async def _find_semantic_seeds(
+    conn,
+    query_embedding_str: str,
+    bank_id: str,
+    fact_type: str,
+    limit: int = 20,
+    threshold: float = 0.3,
+    tags: list[str] | None = None,
+    tags_match: TagsMatch = "any",
+) -> list[RetrievalResult]:
+    """Find semantic seeds via embedding search."""
+    from .tags import build_tags_where_clause_simple
+
+    tags_clause = build_tags_where_clause_simple(tags, 6, match=tags_match)
+    params = [query_embedding_str, bank_id, fact_type, threshold, limit]
+    if tags:
+        params.append(tags)
+
+    rows = await conn.fetch(
+        f"""
+        SELECT id, text, context, event_date, occurred_start, occurred_end,
+               mentioned_at, access_count, embedding, fact_type, document_id, chunk_id, tags,
+               1 - (embedding <=> $1::vector) AS similarity
+        FROM {fq_table("memory_units")}
+        WHERE bank_id = $2
+          AND embedding IS NOT NULL
+          AND fact_type = $3
+          AND (1 - (embedding <=> $1::vector)) >= $4
+          {tags_clause}
+        ORDER BY embedding <=> $1::vector
+        LIMIT $5
+        """,
+        *params,
+    )
+    return [RetrievalResult.from_db_row(dict(r)) for r in rows]
+
+
+class LinkExpansionRetriever(GraphRetriever):
+    """
+    Graph retrieval via direct link expansion from seeds.
+
+    Expands through entity co-occurrence and causal links in a single query.
+    Fast and simple alternative to MPFP.
+    """
+
+    def __init__(
+        self,
+        max_entity_frequency: int = 500,
+        causal_weight_threshold: float = 0.3,
+        causal_limit_per_seed: int = 10,
+    ):
+        """
+        Initialize link expansion retriever.
+
+        Args:
+            max_entity_frequency: Skip entities appearing in more than this many facts
+            causal_weight_threshold: Minimum weight for causal links
+            causal_limit_per_seed: Max causal links to follow per seed
+        """
+        self.max_entity_frequency = max_entity_frequency
+        self.causal_weight_threshold = causal_weight_threshold
+        self.causal_limit_per_seed = causal_limit_per_seed
+
+    @property
+    def name(self) -> str:
+        return "link_expansion"
+
+    async def retrieve(
+        self,
+        pool,
+        query_embedding_str: str,
+        bank_id: str,
+        fact_type: str,
+        budget: int,
+        query_text: str | None = None,
+        semantic_seeds: list[RetrievalResult] | None = None,
+        temporal_seeds: list[RetrievalResult] | None = None,
+        adjacency=None,
+        tags: list[str] | None = None,
+        tags_match: TagsMatch = "any",
+    ) -> tuple[list[RetrievalResult], MPFPTimings | None]:
+        """
+        Retrieve facts by expanding links from seeds.
+
+        Args:
+            pool: Database connection pool
+            query_embedding_str: Query embedding (unused, kept for interface)
+            bank_id: Memory bank ID
+            fact_type: Fact type to filter
+            budget: Maximum results to return
+            query_text: Original query text (unused)
+            semantic_seeds: Pre-computed semantic entry points
+            temporal_seeds: Pre-computed temporal entry points
+            adjacency: Unused, kept for interface compatibility
+            tags: Optional list of tags for visibility filtering (OR matching)
+
+        Returns:
+            Tuple of (results, timings)
+        """
+        start_time = time.time()
+        timings = MPFPTimings(fact_type=fact_type)
+
+        # Use single connection for all queries to reduce pool pressure
+        # (queries are fast ~50ms each, connection acquisition is the bottleneck)
+        async with acquire_with_retry(pool) as conn:
+            # Find seeds if not provided
+            if semantic_seeds:
+                all_seeds = list(semantic_seeds)
+            else:
+                seeds_start = time.time()
+                all_seeds = await _find_semantic_seeds(
+                    conn,
+                    query_embedding_str,
+                    bank_id,
+                    fact_type,
+                    limit=20,
+                    threshold=0.3,
+                    tags=tags,
+                    tags_match=tags_match,
+                )
+                timings.seeds_time = time.time() - seeds_start
+                logger.debug(
+                    f"[LinkExpansion] Found {len(all_seeds)} semantic seeds for fact_type={fact_type} "
+                    f"(tags={tags}, tags_match={tags_match})"
+                )
+
+            # Add temporal seeds if provided
+            if temporal_seeds:
+                all_seeds.extend(temporal_seeds)
+
+            if not all_seeds:
+                logger.debug("[LinkExpansion] No seeds found, returning empty results")
+                return [], timings
+
+            seed_ids = list({s.id for s in all_seeds})
+            timings.pattern_count = len(seed_ids)
+
+            # Run entity and causal expansion sequentially on same connection
+            query_start = time.time()
+
+            entity_rows = await conn.fetch(
+                f"""
+                SELECT
+                    mu.id, mu.text, mu.context, mu.event_date, mu.occurred_start,
+                    mu.occurred_end, mu.mentioned_at, mu.access_count, mu.embedding,
+                    mu.fact_type, mu.document_id, mu.chunk_id, mu.tags,
+                    COUNT(*)::float AS score
+                FROM {fq_table("unit_entities")} seed_ue
+                JOIN {fq_table("entities")} e ON seed_ue.entity_id = e.id
+                JOIN {fq_table("unit_entities")} other_ue ON seed_ue.entity_id = other_ue.entity_id
+                JOIN {fq_table("memory_units")} mu ON other_ue.unit_id = mu.id
+                WHERE seed_ue.unit_id = ANY($1::uuid[])
+                  AND e.mention_count < $2
+                  AND mu.id != ALL($1::uuid[])
+                  AND mu.fact_type = $3
+                GROUP BY mu.id
+                ORDER BY score DESC
+                LIMIT $4
+                """,
+                seed_ids,
+                self.max_entity_frequency,
+                fact_type,
+                budget,
+            )
+
+            causal_rows = await conn.fetch(
+                f"""
+                SELECT DISTINCT ON (mu.id)
+                    mu.id, mu.text, mu.context, mu.event_date, mu.occurred_start,
+                    mu.occurred_end, mu.mentioned_at, mu.access_count, mu.embedding,
+                    mu.fact_type, mu.document_id, mu.chunk_id, mu.tags,
+                    ml.weight + 1.0 AS score
+                FROM {fq_table("memory_links")} ml
+                JOIN {fq_table("memory_units")} mu ON ml.to_unit_id = mu.id
+                WHERE ml.from_unit_id = ANY($1::uuid[])
+                  AND ml.link_type IN ('causes', 'caused_by', 'enables', 'prevents')
+                  AND ml.weight >= $2
+                  AND mu.fact_type = $3
+                ORDER BY mu.id, ml.weight DESC
+                LIMIT $4
+                """,
+                seed_ids,
+                self.causal_weight_threshold,
+                fact_type,
+                budget,
+            )
+
+            timings.edge_load_time = time.time() - query_start
+            timings.db_queries = 2
+            timings.edge_count = len(entity_rows) + len(causal_rows)
+
+        # Merge results, taking max score per fact
+        score_map: dict[str, float] = {}
+        row_map: dict[str, dict] = {}
+
+        for row in entity_rows:
+            fact_id = str(row["id"])
+            score_map[fact_id] = max(score_map.get(fact_id, 0), row["score"])
+            row_map[fact_id] = dict(row)
+
+        for row in causal_rows:
+            fact_id = str(row["id"])
+            score_map[fact_id] = max(score_map.get(fact_id, 0), row["score"])
+            if fact_id not in row_map:
+                row_map[fact_id] = dict(row)
+
+        # Sort by score and limit
+        sorted_ids = sorted(score_map.keys(), key=lambda x: score_map[x], reverse=True)[:budget]
+        rows = [row_map[fact_id] for fact_id in sorted_ids]
+
+        # Convert to results
+        results = []
+        for row in rows:
+            result = RetrievalResult.from_db_row(dict(row))
+            result.activation = row["score"]
+            results.append(result)
+
+        # Apply tags filtering (graph expansion may reach untagged memories)
+        if tags:
+            results = filter_results_by_tags(results, tags, match=tags_match)
+
+        timings.result_count = len(results)
+        timings.traverse = time.time() - start_time
+
+        logger.debug(
+            f"LinkExpansion: {len(results)} results from {len(seed_ids)} seeds "
+            f"in {timings.traverse * 1000:.1f}ms (query: {timings.edge_load_time * 1000:.1f}ms)"
+        )
+
+        return results, timings

hindsight-api/hindsight_api/engine/search/mpfp_retrieval.py

@@ -9,6 +9,7 @@ propagation from Approximate PPR.
 
 Key properties:
 - Sublinear in graph size (threshold pruning bounds active nodes)
+- Lazy edge loading: only loads edges for frontier nodes, not entire graph
 - Predefined patterns capture different retrieval intents
 - All patterns run in parallel, results fused via RRF
 - No LLM in the loop during traversal
@@ -20,8 +21,10 @@ from collections import defaultdict
 from dataclasses import dataclass, field
 
 from ..db_utils import acquire_with_retry
+from ..memory_engine import fq_table
 from .graph_retrieval import GraphRetriever
-from .types import RetrievalResult
+from .tags import TagsMatch
+from .types import MPFPTimings, RetrievalResult
 
 logger = logging.getLogger(__name__)
 
@@ -40,11 +43,27 @@ class EdgeTarget:
 
 
 @dataclass
-class TypedAdjacency:
-    """Adjacency lists split by edge type."""
+class EdgeCache:
+    """
+    Cache for lazily-loaded edges.
 
-    # edge_type -> from_node_id -> list of (to_node_id, weight)
+    Grows per-hop as edges are loaded for frontier nodes.
+    Shared across patterns to avoid redundant loads.
+    Loads ALL edge types at once to minimize DB queries.
+    Thread-safe via asyncio lock to prevent redundant concurrent loads.
+    """
+
+    # edge_type -> from_node_id -> list of EdgeTarget
     graphs: dict[str, dict[str, list[EdgeTarget]]] = field(default_factory=dict)
+    # Track which nodes have been fully loaded (all edge types)
+    _fully_loaded: set[str] = field(default_factory=set)
+    # Timing stats
+    db_queries: int = 0
+    edge_load_time: float = 0.0
+    # Detailed hop timing for debugging
+    hop_details: list[dict] = field(default_factory=list)
+    # Lock to prevent redundant concurrent loads
+    _lock: asyncio.Lock = field(default_factory=asyncio.Lock)
 
     def get_neighbors(self, edge_type: str, node_id: str) -> list[EdgeTarget]:
         """Get neighbors for a node via a specific edge type."""
@@ -62,6 +81,31 @@ class TypedAdjacency:
 
         return [EdgeTarget(node_id=n.node_id, weight=n.weight / total) for n in neighbors]
 
+    def is_fully_loaded(self, node_id: str) -> bool:
+        """Check if all edges for this node have been loaded."""
+        return node_id in self._fully_loaded
+
+    def get_uncached(self, node_ids: list[str]) -> list[str]:
+        """Get node IDs that haven't been fully loaded yet."""
+        return [n for n in node_ids if not self.is_fully_loaded(n)]
+
+    def add_all_edges(self, edges_by_type: dict[str, dict[str, list[EdgeTarget]]], all_queried: list[str]):
+        """
+        Add loaded edges to the cache (all edge types at once).
+
+        Args:
+            edges_by_type: Dict mapping edge_type -> from_node_id -> list of EdgeTarget
+            all_queried: All node IDs that were queried (marks them as fully loaded)
+        """
+        for edge_type, edges in edges_by_type.items():
+            if edge_type not in self.graphs:
+                self.graphs[edge_type] = {}
+            for node_id, neighbors in edges.items():
+                self.graphs[edge_type][node_id] = neighbors
+
+        # Mark all queried nodes as fully loaded (even if they have no edges)
+        self._fully_loaded.update(all_queried)
+
 
 @dataclass
 class PatternResult:
@@ -108,66 +152,249 @@ class SeedNode:
 
 
 # -----------------------------------------------------------------------------
-# Core Algorithm
+# Lazy Edge Loading
 # -----------------------------------------------------------------------------
 
 
-def mpfp_traverse(
-    seeds: list[SeedNode],
-    pattern: list[str],
-    adjacency: TypedAdjacency,
-    config: MPFPConfig,
-) -> PatternResult:
+async def load_all_edges_for_frontier(
+    pool,
+    node_ids: list[str],
+    top_k_per_type: int = 20,
+) -> dict[str, dict[str, list[EdgeTarget]]]:
     """
-    Forward Push traversal following a meta-path pattern.
+    Load top-k edges per (node, edge_type) for frontier nodes.
+
+    Uses a LATERAL join to efficiently fetch only the top-k edges per type,
+    avoiding loading hundreds of entity edges when only 20 are needed.
+
+    Requires composite index: (from_unit_id, link_type, weight DESC)
 
     Args:
-        seeds: Entry point nodes with initial scores
-        pattern: Sequence of edge types to follow
-        adjacency: Typed adjacency structure
-        config: Algorithm parameters
+        pool: Database connection pool
+        node_ids: Frontier node IDs to load edges for
+        top_k_per_type: Max edges to load per (node, link_type) pair
 
     Returns:
-        PatternResult with accumulated scores per node
+        Dict mapping edge_type -> from_node_id -> list of EdgeTarget
+    """
+    if not node_ids:
+        return {}
+
+    async with acquire_with_retry(pool) as conn:
+        # Use LATERAL join to get top-k per (from_node, link_type)
+        # This leverages the composite index for efficient early termination
+        rows = await conn.fetch(
+            f"""
+            WITH frontier(node_id) AS (SELECT unnest($1::uuid[]))
+            SELECT f.node_id as from_unit_id, lt.link_type, edges.to_unit_id, edges.weight
+            FROM frontier f
+            CROSS JOIN (VALUES ('semantic'), ('temporal'), ('entity'), ('causes'), ('caused_by')) AS lt(link_type)
+            CROSS JOIN LATERAL (
+                SELECT ml.to_unit_id, ml.weight
+                FROM {fq_table("memory_links")} ml
+                WHERE ml.from_unit_id = f.node_id
+                  AND ml.link_type = lt.link_type
+                  AND ml.weight >= 0.1
+                ORDER BY ml.weight DESC
+                LIMIT $2
+            ) edges
+            """,
+            node_ids,
+            top_k_per_type,
+        )
+
+    # Group by edge_type -> from_node -> neighbors
+    result: dict[str, dict[str, list[EdgeTarget]]] = defaultdict(lambda: defaultdict(list))
+    for row in rows:
+        edge_type = row["link_type"]
+        from_id = str(row["from_unit_id"])
+        to_id = str(row["to_unit_id"])
+        weight = row["weight"]
+        result[edge_type][from_id].append(EdgeTarget(node_id=to_id, weight=weight))
+
+    # Convert nested defaultdicts to regular dicts
+    return {edge_type: dict(edges) for edge_type, edges in result.items()}
+
+
+# -----------------------------------------------------------------------------
+# Core Algorithm (Async with Lazy Loading)
+# -----------------------------------------------------------------------------
+
+
+@dataclass
+class PatternState:
+    """State for a pattern traversal between hops."""
+
+    pattern: list[str]
+    hop_index: int
+    scores: dict[str, float]
+    frontier: dict[str, float]
+
+
+def _init_pattern_state(seeds: list[SeedNode], pattern: list[str]) -> PatternState:
+    """Initialize pattern state from seeds."""
+    if not seeds:
+        return PatternState(pattern=pattern, hop_index=0, scores={}, frontier={})
+
+    total_seed_score = sum(s.score for s in seeds)
+    if total_seed_score == 0:
+        total_seed_score = len(seeds)
+
+    frontier = {s.node_id: s.score / total_seed_score for s in seeds}
+    return PatternState(pattern=pattern, hop_index=0, scores={}, frontier=frontier)
+
+
+def _execute_hop(state: PatternState, cache: EdgeCache, config: MPFPConfig) -> set[str]:
+    """
+    Execute ONE hop of traversal, return frontier nodes for next hop.
+
+    This is a pure function that uses cached edges (no DB access).
+    Returns set of uncached nodes needed for next hop.
+    """
+    if state.hop_index >= len(state.pattern):
+        return set()
+
+    edge_type = state.pattern[state.hop_index]
+
+    # Collect active nodes above threshold
+    active_nodes = [node_id for node_id, mass in state.frontier.items() if mass >= config.threshold]
+    if not active_nodes:
+        state.frontier = {}
+        return set()
+
+    # Propagate mass using cached edges
+    next_frontier: dict[str, float] = {}
+    uncached_for_next: set[str] = set()
+
+    for node_id, mass in state.frontier.items():
+        if mass < config.threshold:
+            continue
+
+        # Keep α portion for this node
+        state.scores[node_id] = state.scores.get(node_id, 0) + config.alpha * mass
+
+        # Push (1-α) to neighbors
+        push_mass = (1 - config.alpha) * mass
+        neighbors = cache.get_normalized_neighbors(edge_type, node_id, config.top_k_neighbors)
+
+        for neighbor in neighbors:
+            next_frontier[neighbor.node_id] = next_frontier.get(neighbor.node_id, 0) + push_mass * neighbor.weight
+            # Track if we'll need edges for this node in the next hop
+            if not cache.is_fully_loaded(neighbor.node_id):
+                uncached_for_next.add(neighbor.node_id)
+
+    state.frontier = next_frontier
+    state.hop_index += 1
+
+    return uncached_for_next
+
+
+def _finalize_pattern(state: PatternState, config: MPFPConfig) -> PatternResult:
+    """Finalize pattern by adding remaining frontier mass to scores."""
+    for node_id, mass in state.frontier.items():
+        if mass >= config.threshold:
+            state.scores[node_id] = state.scores.get(node_id, 0) + mass
+
+    return PatternResult(pattern=state.pattern, scores=state.scores)
+
+
+async def mpfp_traverse_hop_synchronized(
+    pool,
+    pattern_jobs: list[tuple[list[SeedNode], list[str]]],
+    config: MPFPConfig,
+    cache: EdgeCache,
+) -> list[PatternResult]:
+    """
+    Execute ALL patterns with hop-synchronized edge loading.
+
+    Instead of running each pattern independently (causing multiple DB queries),
+    this function:
+    1. Runs hop 1 for ALL patterns (using pre-warmed seed edges)
+    2. Collects ALL unique hop-2 frontier nodes across patterns
+    3. Pre-warms hop-2 edges in ONE query
+    4. Runs hop 2 for ALL patterns
+
+    This reduces DB queries from O(patterns * hops) to O(hops).
+
+    Args:
+        pool: Database connection pool
+        pattern_jobs: List of (seeds, pattern) tuples
+        config: Algorithm parameters
+        cache: Shared edge cache (should be pre-warmed with seed edges)
+
+    Returns:
+        List of PatternResult for each pattern
+    """
+    import time
+
+    # Initialize all pattern states
+    states = [_init_pattern_state(seeds, pattern) for seeds, pattern in pattern_jobs]
+
+    # Determine max hops (all patterns should be same length, but be safe)
+    max_hops = max((len(p) for _, p in pattern_jobs), default=0)
+
+    # Detailed timing for debugging
+    hop_times: list[dict] = []
+
+    # Execute hop-by-hop across ALL patterns
+    for hop in range(max_hops):
+        hop_start = time.time()
+        hop_timing = {"hop": hop, "patterns_executed": 0, "uncached_count": 0, "load_time": 0.0}
+
+        # Execute this hop for all patterns, collect uncached nodes for next hop
+        all_uncached: set[str] = set()
+        exec_start = time.time()
+        for state in states:
+            if state.hop_index < len(state.pattern):
+                uncached = _execute_hop(state, cache, config)
+                all_uncached.update(uncached)
+                hop_timing["patterns_executed"] += 1
+        hop_timing["exec_time"] = time.time() - exec_start
+
+        # Pre-warm edges for ALL uncached nodes before next hop
+        hop_timing["uncached_count"] = len(all_uncached)
+        if all_uncached:
+            uncached_list = list(all_uncached - cache._fully_loaded)
+            hop_timing["uncached_after_filter"] = len(uncached_list)
+            if uncached_list:
+                load_start = time.time()
+                edges_by_type = await load_all_edges_for_frontier(pool, uncached_list, config.top_k_neighbors)
+                hop_timing["load_time"] = time.time() - load_start
+                cache.edge_load_time += hop_timing["load_time"]
+                cache.db_queries += 1
+                cache.add_all_edges(edges_by_type, uncached_list)
+                hop_timing["edges_loaded"] = sum(
+                    len(neighbors) for edges in edges_by_type.values() for neighbors in edges.values()
+                )
+
+        hop_timing["total_time"] = time.time() - hop_start
+        hop_times.append(hop_timing)
+
+    # Store hop timing details in cache for logging
+    cache.hop_details = hop_times
+
+    # Finalize all patterns
+    return [_finalize_pattern(state, config) for state in states]
+
+
+async def mpfp_traverse_async(
+    pool,
+    seeds: list[SeedNode],
+    pattern: list[str],
+    config: MPFPConfig,
+    cache: EdgeCache,
+) -> PatternResult:
+    """
+    Async Forward Push traversal with lazy edge loading.
+
+    NOTE: For better performance with multiple patterns, use mpfp_traverse_hop_synchronized().
+    This function is kept for single-pattern use cases.
     """
     if not seeds:
         return PatternResult(pattern=pattern, scores={})
 
-    scores: dict[str, float] = {}
-
-    # Initialize frontier with seed masses (normalized)
-    total_seed_score = sum(s.score for s in seeds)
-    if total_seed_score == 0:
-        total_seed_score = len(seeds)  # fallback to uniform
-
-    frontier: dict[str, float] = {s.node_id: s.score / total_seed_score for s in seeds}
-
-    # Follow pattern hop by hop
-    for edge_type in pattern:
-        next_frontier: dict[str, float] = {}
-
-        for node_id, mass in frontier.items():
-            if mass < config.threshold:
-                continue
-
-            # Keep α portion for this node
-            scores[node_id] = scores.get(node_id, 0) + config.alpha * mass
-
-            # Push (1-α) to neighbors
-            push_mass = (1 - config.alpha) * mass
-            neighbors = adjacency.get_normalized_neighbors(edge_type, node_id, config.top_k_neighbors)
-
-            for neighbor in neighbors:
-                next_frontier[neighbor.node_id] = next_frontier.get(neighbor.node_id, 0) + push_mass * neighbor.weight
-
-        frontier = next_frontier
-
-    # Final frontier nodes get their remaining mass
-    for node_id, mass in frontier.items():
-        if mass >= config.threshold:
-            scores[node_id] = scores.get(node_id, 0) + mass
-
-    return PatternResult(pattern=pattern, scores=scores)
+    results = await mpfp_traverse_hop_synchronized(pool, [(seeds, pattern)], config, cache)
+    return results[0] if results else PatternResult(pattern=pattern, scores={})
 
 
 def rrf_fusion(
@@ -209,38 +436,6 @@ def rrf_fusion(
 # -----------------------------------------------------------------------------
 
 
-async def load_typed_adjacency(pool, bank_id: str) -> TypedAdjacency:
-    """
-    Load all edges for a bank, split by edge type.
-
-    Single query, then organize in-memory for fast traversal.
-    """
-    async with acquire_with_retry(pool) as conn:
-        rows = await conn.fetch(
-            """
-            SELECT ml.from_unit_id, ml.to_unit_id, ml.link_type, ml.weight
-            FROM memory_links ml
-            JOIN memory_units mu ON ml.from_unit_id = mu.id
-            WHERE mu.bank_id = $1
-              AND ml.weight >= 0.1
-            ORDER BY ml.from_unit_id, ml.weight DESC
-            """,
-            bank_id,
-        )
-
-    graphs: dict[str, dict[str, list[EdgeTarget]]] = defaultdict(lambda: defaultdict(list))
-
-    for row in rows:
-        from_id = str(row["from_unit_id"])
-        to_id = str(row["to_unit_id"])
-        link_type = row["link_type"]
-        weight = row["weight"]
-
-        graphs[link_type][from_id].append(EdgeTarget(node_id=to_id, weight=weight))
-
-    return TypedAdjacency(graphs=dict(graphs))
-
-
 async def fetch_memory_units_by_ids(
     pool,
     node_ids: list[str],
@@ -252,10 +447,10 @@ async def fetch_memory_units_by_ids(
 
     async with acquire_with_retry(pool) as conn:
         rows = await conn.fetch(
-            """
+            f"""
             SELECT id, text, context, event_date, occurred_start, occurred_end,
-                   mentioned_at, access_count, embedding, fact_type, document_id, chunk_id
-            FROM memory_units
+                   mentioned_at, access_count, embedding, fact_type, document_id, chunk_id, tags
+            FROM {fq_table("memory_units")}
             WHERE id = ANY($1::uuid[])
               AND fact_type = $2
             """,
@@ -273,10 +468,10 @@ async def fetch_memory_units_by_ids(
 
 class MPFPGraphRetriever(GraphRetriever):
     """
-    Graph retrieval using Meta-Path Forward Push.
+    Graph retrieval using Meta-Path Forward Push with lazy edge loading.
 
     Runs predefined patterns in parallel from semantic and temporal seeds,
-    then fuses results via RRF.
+    loading edges on-demand per hop instead of loading entire graph upfront.
     """
 
     def __init__(self, config: MPFPConfig | None = None):
@@ -286,8 +481,13 @@ class MPFPGraphRetriever(GraphRetriever):
         Args:
             config: Algorithm configuration (uses defaults if None)
         """
-        self.config = config or MPFPConfig()
-        self._adjacency_cache: dict[str, TypedAdjacency] = {}
+        if config is None:
+            # Read top_k_neighbors from global config
+            from ...config import get_config
+
+            global_config = get_config()
+            config = MPFPConfig(top_k_neighbors=global_config.mpfp_top_k_neighbors)
+        self.config = config
 
     @property
     def name(self) -> str:
@@ -303,9 +503,12 @@ class MPFPGraphRetriever(GraphRetriever):
         query_text: str | None = None,
         semantic_seeds: list[RetrievalResult] | None = None,
         temporal_seeds: list[RetrievalResult] | None = None,
-    ) -> list[RetrievalResult]:
+        adjacency=None,  # Ignored - kept for interface compatibility
+        tags: list[str] | None = None,
+        tags_match: TagsMatch = "any",
+    ) -> tuple[list[RetrievalResult], MPFPTimings | None]:
         """
-        Retrieve facts using MPFP algorithm.
+        Retrieve facts using MPFP algorithm with lazy edge loading.
 
         Args:
             pool: Database connection pool
@@ -316,12 +519,15 @@ class MPFPGraphRetriever(GraphRetriever):
             query_text: Original query text (optional)
             semantic_seeds: Pre-computed semantic entry points
             temporal_seeds: Pre-computed temporal entry points
+            adjacency: Ignored (kept for interface compatibility)
+            tags: Optional list of tags for visibility filtering (OR matching)
 
         Returns:
-            List of RetrievalResult with activation scores
+            Tuple of (List of RetrievalResult with activation scores, MPFPTimings)
         """
-        # Load typed adjacency (could cache per bank_id with TTL)
-        adjacency = await load_typed_adjacency(pool, bank_id)
+        import time
+
+        timings = MPFPTimings(fact_type=fact_type)
 
         # Convert seeds to SeedNode format
         semantic_seed_nodes = self._convert_seeds(semantic_seeds, "similarity")
@@ -329,54 +535,88 @@ class MPFPGraphRetriever(GraphRetriever):
 
         # If no semantic seeds provided, fall back to finding our own
         if not semantic_seed_nodes:
-            semantic_seed_nodes = await self._find_semantic_seeds(pool, query_embedding_str, bank_id, fact_type)
+            seeds_start = time.time()
+            semantic_seed_nodes = await self._find_semantic_seeds(
+                pool, query_embedding_str, bank_id, fact_type, tags=tags, tags_match=tags_match
+            )
+            timings.seeds_time = time.time() - seeds_start
+            logger.debug(
+                f"[MPFP] Found {len(semantic_seed_nodes)} semantic seeds for fact_type={fact_type} (tags={tags}, tags_match={tags_match})"
+            )
 
-        # Run all patterns in parallel
-        tasks = []
+        # Collect all pattern jobs
+        pattern_jobs = []
 
         # Patterns from semantic seeds
         for pattern in self.config.patterns_semantic:
             if semantic_seed_nodes:
-                tasks.append(
-                    asyncio.to_thread(
-                        mpfp_traverse,
-                        semantic_seed_nodes,
-                        pattern,
-                        adjacency,
-                        self.config,
-                    )
-                )
+                pattern_jobs.append((semantic_seed_nodes, pattern))
 
         # Patterns from temporal seeds
         for pattern in self.config.patterns_temporal:
             if temporal_seed_nodes:
-                tasks.append(
-                    asyncio.to_thread(
-                        mpfp_traverse,
-                        temporal_seed_nodes,
-                        pattern,
-                        adjacency,
-                        self.config,
-                    )
-                )
+                pattern_jobs.append((temporal_seed_nodes, pattern))
 
-        if not tasks:
-            return []
+        if not pattern_jobs:
+            logger.debug(
+                f"[MPFP] No pattern jobs (semantic_seeds={len(semantic_seed_nodes)}, temporal_seeds={len(temporal_seed_nodes)})"
+            )
+            return [], timings
 
-        # Gather pattern results
-        pattern_results = await asyncio.gather(*tasks)
+        timings.pattern_count = len(pattern_jobs)
+
+        # Shared edge cache across all patterns
+        cache = EdgeCache()
+
+        # Pre-warm cache with ALL seed node edges BEFORE running patterns
+        # This prevents redundant DB queries at hop 1
+        all_seed_ids = list({s.node_id for seeds, _ in pattern_jobs for s in seeds})
+        if all_seed_ids:
+            import time as time_module
+
+            prewarm_start = time_module.time()
+            edges_by_type = await load_all_edges_for_frontier(pool, all_seed_ids, self.config.top_k_neighbors)
+            cache.edge_load_time += time_module.time() - prewarm_start
+            cache.db_queries += 1
+            cache.add_all_edges(edges_by_type, all_seed_ids)
+
+        # Run all patterns with HOP-SYNCHRONIZED edge loading
+        # This batches hop-2 edge loads across ALL patterns into ONE query
+        # Reduces DB queries from O(patterns * hops) to O(hops)
+        step_start = time.time()
+        pattern_results = await mpfp_traverse_hop_synchronized(pool, pattern_jobs, self.config, cache)
+        timings.traverse = time.time() - step_start
+
+        # Record edge loading stats from cache
+        timings.edge_count = sum(len(neighbors) for g in cache.graphs.values() for neighbors in g.values())
+        timings.db_queries = cache.db_queries
+        timings.edge_load_time = cache.edge_load_time
+        timings.hop_details = cache.hop_details
 
         # Fuse results
+        step_start = time.time()
         fused = rrf_fusion(pattern_results, top_k=budget)
+        timings.fusion = time.time() - step_start
 
         if not fused:
-            return []
+            logger.debug(f"[MPFP] No fused results after RRF fusion (pattern_count={len(pattern_results)})")
+            return [], timings
 
-        # Get top result IDs (don't exclude seeds - they may be highly relevant)
+        # Get top result IDs
         result_ids = [node_id for node_id, score in fused][:budget]
 
         # Fetch full details
+        step_start = time.time()
         results = await fetch_memory_units_by_ids(pool, result_ids, fact_type)
+        timings.fetch = time.time() - step_start
+
+        # Filter results by tags (graph traversal may have picked up unfiltered memories)
+        if tags:
+            from .tags import filter_results_by_tags
+
+            results = filter_results_by_tags(results, tags, match=tags_match)
+
+        timings.result_count = len(results)
 
         # Add activation scores from fusion
         score_map = {node_id: score for node_id, score in fused}
@@ -386,7 +626,7 @@ class MPFPGraphRetriever(GraphRetriever):
         # Sort by activation
         results.sort(key=lambda r: r.activation or 0, reverse=True)
 
-        return results
+        return results, timings
 
     def _convert_seeds(
         self,
@@ -414,25 +654,31 @@ class MPFPGraphRetriever(GraphRetriever):
         fact_type: str,
         limit: int = 20,
         threshold: float = 0.3,
+        tags: list[str] | None = None,
+        tags_match: TagsMatch = "any",
     ) -> list[SeedNode]:
         """Fallback: find semantic seeds via embedding search."""
+        from .tags import build_tags_where_clause_simple
+
+        tags_clause = build_tags_where_clause_simple(tags, 6, match=tags_match)
+        params = [query_embedding_str, bank_id, fact_type, threshold, limit]
+        if tags:
+            params.append(tags)
+
         async with acquire_with_retry(pool) as conn:
             rows = await conn.fetch(
-                """
+                f"""
                 SELECT id, 1 - (embedding <=> $1::vector) AS similarity
-                FROM memory_units
+                FROM {fq_table("memory_units")}
                 WHERE bank_id = $2
                   AND embedding IS NOT NULL
                   AND fact_type = $3
                   AND (1 - (embedding <=> $1::vector)) >= $4
+                  {tags_clause}
                 ORDER BY embedding <=> $1::vector
                 LIMIT $5
                 """,
-                query_embedding_str,
-                bank_id,
-                fact_type,
-                threshold,
-                limit,
+                *params,
             )
 
         return [SeedNode(node_id=str(r["id"]), score=r["similarity"]) for r in rows]

hindsight-api/hindsight_api/engine/search/observation_utils.py

@@ -1,125 +0,0 @@
-"""
-Observation utilities for generating entity observations from facts.
-
-Observations are objective facts synthesized from multiple memory facts
-about an entity, without personality influence.
-"""
-
-import logging
-
-from pydantic import BaseModel, Field
-
-from ..response_models import MemoryFact
-
-logger = logging.getLogger(__name__)
-
-
-class Observation(BaseModel):
-    """An observation about an entity."""
-
-    observation: str = Field(description="The observation text - a factual statement about the entity")
-
-
-class ObservationExtractionResponse(BaseModel):
-    """Response containing extracted observations."""
-
-    observations: list[Observation] = Field(default_factory=list, description="List of observations about the entity")
-
-
-def format_facts_for_observation_prompt(facts: list[MemoryFact]) -> str:
-    """Format facts as text for observation extraction prompt."""
-    import json
-
-    if not facts:
-        return "[]"
-    formatted = []
-    for fact in facts:
-        fact_obj = {"text": fact.text}
-
-        # Add context if available
-        if fact.context:
-            fact_obj["context"] = fact.context
-
-        # Add occurred_start if available
-        if fact.occurred_start:
-            fact_obj["occurred_at"] = fact.occurred_start
-
-        formatted.append(fact_obj)
-
-    return json.dumps(formatted, indent=2)
-
-
-def build_observation_prompt(
-    entity_name: str,
-    facts_text: str,
-) -> str:
-    """Build the observation extraction prompt for the LLM."""
-    return f"""Based on the following facts about "{entity_name}", generate a list of key observations.
-
-FACTS ABOUT {entity_name.upper()}:
-{facts_text}
-
-Your task: Synthesize the facts into clear, objective observations about {entity_name}.
-
-GUIDELINES:
-1. Each observation should be a factual statement about {entity_name}
-2. Combine related facts into single observations where appropriate
-3. Be objective - do not add opinions, judgments, or interpretations
-4. Focus on what we KNOW about {entity_name}, not what we assume
-5. Include observations about: identity, characteristics, roles, relationships, activities
-6. Write in third person (e.g., "John is..." not "I think John is...")
-7. If there are conflicting facts, note the most recent or most supported one
-
-EXAMPLES of good observations:
-- "John works at Google as a software engineer"
-- "John is detail-oriented and methodical in his approach"
-- "John collaborates frequently with Sarah on the AI project"
-- "John joined the company in 2023"
-
-EXAMPLES of bad observations (avoid these):
-- "John seems like a good person" (opinion/judgment)
-- "John probably likes his job" (assumption)
-- "I believe John is reliable" (first-person opinion)
-
-Generate 3-7 observations based on the available facts. If there are very few facts, generate fewer observations."""
-
-
-def get_observation_system_message() -> str:
-    """Get the system message for observation extraction."""
-    return "You are an objective observer synthesizing facts about an entity. Generate clear, factual observations without opinions or personality influence. Be concise and accurate."
-
-
-async def extract_observations_from_facts(llm_config, entity_name: str, facts: list[MemoryFact]) -> list[str]:
-    """
-    Extract observations from facts about an entity using LLM.
-
-    Args:
-        llm_config: LLM configuration to use
-        entity_name: Name of the entity to generate observations about
-        facts: List of facts mentioning the entity
-
-    Returns:
-        List of observation strings
-    """
-    if not facts:
-        return []
-
-    facts_text = format_facts_for_observation_prompt(facts)
-    prompt = build_observation_prompt(entity_name, facts_text)
-
-    try:
-        result = await llm_config.call(
-            messages=[
-                {"role": "system", "content": get_observation_system_message()},
-                {"role": "user", "content": prompt},
-            ],
-            response_format=ObservationExtractionResponse,
-            scope="memory_extract_observation",
-        )
-
-        observations = [op.observation for op in result.observations]
-        return observations
-
-    except Exception as e:
-        logger.warning(f"Failed to extract observations for {entity_name}: {str(e)}")
-        return []

hindsight-api/hindsight_api/engine/search/reranking.py

@@ -26,8 +26,25 @@ class CrossEncoderReranker:
 
             cross_encoder = create_cross_encoder_from_env()
         self.cross_encoder = cross_encoder
+        self._initialized = False
 
-    def rerank(self, query: str, candidates: list[MergedCandidate]) -> list[ScoredResult]:
+    async def ensure_initialized(self):
+        """Ensure the cross-encoder model is initialized (for lazy initialization)."""
+        if self._initialized:
+            return
+
+        import asyncio
+
+        cross_encoder = self.cross_encoder
+        # For local providers, run in thread pool to avoid blocking event loop
+        if cross_encoder.provider_name == "local":
+            loop = asyncio.get_event_loop()
+            await loop.run_in_executor(None, lambda: asyncio.run(cross_encoder.initialize()))
+        else:
+            await cross_encoder.initialize()
+        self._initialized = True
+
+    async def rerank(self, query: str, candidates: list[MergedCandidate]) -> list[ScoredResult]:
         """
         Rerank candidates using cross-encoder scores.
 
@@ -68,7 +85,7 @@ class CrossEncoderReranker:
             pairs.append([query, doc_text])
 
         # Get cross-encoder scores
-        scores = self.cross_encoder.predict(pairs)
+        scores = await self.cross_encoder.predict(pairs)
 
         # Normalize scores using sigmoid to [0, 1] range
         # Cross-encoder returns logits which can be negative

hindsight-api/hindsight_api/engine/search/tags.py

@@ -0,0 +1,172 @@
+"""
+Tags filtering utilities for retrieval.
+
+Provides SQL building functions for filtering memories by tags.
+Supports four matching modes via TagsMatch enum:
+- "any": OR matching, includes untagged memories (default, backward compatible)
+- "all": AND matching, includes untagged memories
+- "any_strict": OR matching, excludes untagged memories
+- "all_strict": AND matching, excludes untagged memories
+
+OR matching (any/any_strict): Memory matches if ANY of its tags overlap with request tags
+AND matching (all/all_strict): Memory matches if ALL request tags are present in its tags
+"""
+
+from typing import Literal
+
+TagsMatch = Literal["any", "all", "any_strict", "all_strict"]
+
+
+def _parse_tags_match(match: TagsMatch) -> tuple[str, bool]:
+    """
+    Parse TagsMatch into operator and include_untagged flag.
+
+    Returns:
+        Tuple of (operator, include_untagged)
+        - operator: "&&" for any/any_strict, "@>" for all/all_strict
+        - include_untagged: True for any/all, False for any_strict/all_strict
+    """
+    if match == "any":
+        return "&&", True
+    elif match == "all":
+        return "@>", True
+    elif match == "any_strict":
+        return "&&", False
+    elif match == "all_strict":
+        return "@>", False
+    else:
+        # Default to "any" behavior
+        return "&&", True
+
+
+def build_tags_where_clause(
+    tags: list[str] | None,
+    param_offset: int = 1,
+    table_alias: str = "",
+    match: TagsMatch = "any",
+) -> tuple[str, list, int]:
+    """
+    Build a SQL WHERE clause for filtering by tags.
+
+    Supports four matching modes:
+    - "any" (default): OR matching, includes untagged memories
+    - "all": AND matching, includes untagged memories
+    - "any_strict": OR matching, excludes untagged memories
+    - "all_strict": AND matching, excludes untagged memories
+
+    Args:
+        tags: List of tags to filter by. If None or empty, returns empty clause (no filtering).
+        param_offset: Starting parameter number for SQL placeholders (default 1).
+        table_alias: Optional table alias prefix (e.g., "mu." for "memory_units mu").
+        match: Matching mode. Defaults to "any".
+
+    Returns:
+        Tuple of (sql_clause, params, next_param_offset):
+        - sql_clause: SQL WHERE clause string
+        - params: List of parameter values to bind
+        - next_param_offset: Next available parameter number
+
+    Example:
+        >>> clause, params, next_offset = build_tags_where_clause(['user_a'], 3, 'mu.', 'any_strict')
+        >>> print(clause)  # "AND mu.tags IS NOT NULL AND mu.tags != '{}' AND mu.tags && $3"
+    """
+    if not tags:
+        return "", [], param_offset
+
+    column = f"{table_alias}tags" if table_alias else "tags"
+    operator, include_untagged = _parse_tags_match(match)
+
+    if include_untagged:
+        # Include untagged memories (NULL or empty array) OR matching tags
+        clause = f"AND ({column} IS NULL OR {column} = '{{}}' OR {column} {operator} ${param_offset})"
+    else:
+        # Strict: only memories with matching tags (exclude NULL and empty)
+        clause = f"AND {column} IS NOT NULL AND {column} != '{{}}' AND {column} {operator} ${param_offset}"
+
+    return clause, [tags], param_offset + 1
+
+
+def build_tags_where_clause_simple(
+    tags: list[str] | None,
+    param_num: int,
+    table_alias: str = "",
+    match: TagsMatch = "any",
+) -> str:
+    """
+    Build a simple SQL WHERE clause for tags filtering.
+
+    This is a convenience version that returns just the clause string,
+    assuming the caller will add the tags array to their params list.
+
+    Args:
+        tags: List of tags to filter by. If None or empty, returns empty string.
+        param_num: Parameter number to use in the clause.
+        table_alias: Optional table alias prefix.
+        match: Matching mode. Defaults to "any".
+
+    Returns:
+        SQL clause string or empty string.
+    """
+    if not tags:
+        return ""
+
+    column = f"{table_alias}tags" if table_alias else "tags"
+    operator, include_untagged = _parse_tags_match(match)
+
+    if include_untagged:
+        # Include untagged memories (NULL or empty array) OR matching tags
+        return f"AND ({column} IS NULL OR {column} = '{{}}' OR {column} {operator} ${param_num})"
+    else:
+        # Strict: only memories with matching tags (exclude NULL and empty)
+        return f"AND {column} IS NOT NULL AND {column} != '{{}}' AND {column} {operator} ${param_num}"
+
+
+def filter_results_by_tags(
+    results: list,
+    tags: list[str] | None,
+    match: TagsMatch = "any",
+) -> list:
+    """
+    Filter retrieval results by tags in Python (for post-processing).
+
+    Used when SQL filtering isn't possible (e.g., graph traversal results).
+
+    Args:
+        results: List of RetrievalResult objects with a 'tags' attribute.
+        tags: List of tags to filter by. If None or empty, returns all results.
+        match: Matching mode. Defaults to "any".
+
+    Returns:
+        Filtered list of results.
+    """
+    if not tags:
+        return results
+
+    _, include_untagged = _parse_tags_match(match)
+    is_any_match = match in ("any", "any_strict")
+
+    tags_set = set(tags)
+    filtered = []
+
+    for result in results:
+        result_tags = getattr(result, "tags", None)
+
+        # Check if untagged
+        is_untagged = result_tags is None or len(result_tags) == 0
+
+        if is_untagged:
+            if include_untagged:
+                filtered.append(result)
+            # else: skip untagged
+        else:
+            result_tags_set = set(result_tags)
+            if is_any_match:
+                # Any overlap
+                if result_tags_set & tags_set:
+                    filtered.append(result)
+            else:
+                # All tags must be present
+                if tags_set <= result_tags_set:
+                    filtered.append(result)
+
+    return filtered

hindsight-api/hindsight_api/engine/search/think_utils.py

@@ -3,31 +3,13 @@ Think operation utilities for formulating answers based on agent and world facts
 """
 
 import logging
-import re
 from datetime import datetime
 
-from pydantic import BaseModel, Field
-
 from ..response_models import DispositionTraits, MemoryFact
 
 logger = logging.getLogger(__name__)
 
 
-class Opinion(BaseModel):
-    """An opinion formed by the bank."""
-
-    opinion: str = Field(description="The opinion or perspective with reasoning included")
-    confidence: float = Field(description="Confidence score for this opinion (0.0 to 1.0, where 1.0 is very confident)")
-
-
-class OpinionExtractionResponse(BaseModel):
-    """Response containing extracted opinions."""
-
-    opinions: list[Opinion] = Field(
-        default_factory=list, description="List of opinions formed with their supporting reasons and confidence scores"
-    )
-
-
 def describe_trait_level(value: int) -> str:
     """Convert trait value (1-5) to descriptive text."""
     levels = {1: "very low", 2: "low", 3: "moderate", 4: "high", 5: "very high"}
@@ -93,17 +75,46 @@ def format_facts_for_prompt(facts: list[MemoryFact]) -> str:
     return json.dumps(formatted, indent=2)
 
 
+def format_entity_summaries_for_prompt(entities: dict) -> str:
+    """Format entity summaries for inclusion in the reflect prompt.
+
+    Args:
+        entities: Dict mapping entity name to EntityState objects
+
+    Returns:
+        Formatted string with entity summaries, or empty string if no summaries
+    """
+    if not entities:
+        return ""
+
+    summaries = []
+    for name, state in entities.items():
+        # Get summary from observations (summary is stored as single observation)
+        if state.observations:
+            summary_text = state.observations[0].text
+            summaries.append(f"## {name}\n{summary_text}")
+
+    if not summaries:
+        return ""
+
+    return "\n\n".join(summaries)
+
+
 def build_think_prompt(
     agent_facts_text: str,
     world_facts_text: str,
-    opinion_facts_text: str,
     query: str,
     name: str,
     disposition: DispositionTraits,
     background: str,
-    context: str = None,
+    context: str | None = None,
+    entity_summaries_text: str | None = None,
 ) -> str:
-    """Build the think prompt for the LLM."""
+    """Build the think prompt for the LLM.
+
+    Note: opinion_facts_text parameter removed - opinions are now stored as mental models
+    and included via entity_summaries_text.
+    """
     disposition_desc = build_disposition_description(disposition)
 
     name_section = f"""
@@ -125,6 +136,14 @@ Your background:
 ADDITIONAL CONTEXT:
 {context}
 
+"""
+
+    entity_section = ""
+    if entity_summaries_text:
+        entity_section = f"""
+KEY PEOPLE, PLACES & THINGS I KNOW ABOUT:
+{entity_summaries_text}
+
 """
 
     return f"""Here's what I know and have experienced:
@@ -135,14 +154,11 @@ MY IDENTITY & EXPERIENCES:
 WHAT I KNOW ABOUT THE WORLD:
 {world_facts_text}
 
-MY EXISTING OPINIONS & BELIEFS:
-{opinion_facts_text}
-
-{context_section}{name_section}{disposition_desc}{background_section}
+{entity_section}{context_section}{name_section}{disposition_desc}{background_section}
 
 QUESTION: {query}
 
-Based on everything I know, believe, and who I am (including my name, disposition and background), here's what I genuinely think about this question. I'll draw on my experiences, knowledge, opinions, and personal traits to give you my honest perspective."""
+Based on everything I know, believe, and who I am (including my name, disposition and background), here's what I genuinely think about this question. I'll draw on my experiences, knowledge, and personal traits to give you my honest perspective."""
 
 
 def get_system_message(disposition: DispositionTraits) -> str:
@@ -172,117 +188,7 @@ def get_system_message(disposition: DispositionTraits) -> str:
         " ".join(instructions) if instructions else "Balance your disposition traits when interpreting information."
     )
 
-    return f"You are a person with your own thoughts, experiences, opinions, and disposition. When asked a question, respond naturally like a human would - share what you genuinely think based on what you know and have experienced. {disposition_instruction} Be direct, express your views confidently, and use 'I think', 'I believe', 'in my view', etc. Respond in plain text without markdown formatting."
-
-
-async def extract_opinions_from_text(llm_config, text: str, query: str) -> list[Opinion]:
-    """
-    Extract opinions with reasons and confidence from text using LLM.
-
-    Args:
-        llm_config: LLM configuration to use
-        text: Text to extract opinions from
-        query: The original query that prompted this response
-
-    Returns:
-        List of Opinion objects with text and confidence
-    """
-    extraction_prompt = f"""Extract any NEW opinions or perspectives from the answer below and rewrite them in FIRST-PERSON as if YOU are stating the opinion directly.
-
-ORIGINAL QUESTION:
-{query}
-
-ANSWER PROVIDED:
-{text}
-
-Your task: Find opinions in the answer and rewrite them AS IF YOU ARE THE ONE SAYING THEM.
-
-An opinion is a judgment, viewpoint, or conclusion that goes beyond just stating facts.
-
-IMPORTANT: Do NOT extract statements like:
-- "I don't have enough information"
-- "The facts don't contain information about X"
-- "I cannot answer because..."
-
-ONLY extract actual opinions about substantive topics.
-
-CRITICAL FORMAT REQUIREMENTS:
-1. **ALWAYS start with first-person phrases**: "I think...", "I believe...", "In my view...", "I've come to believe...", "Previously I thought... but now..."
-2. **NEVER use third-person**: Do NOT say "The speaker thinks..." or "They believe..." - always use "I"
-3. Include the reasoning naturally within the statement
-4. Provide a confidence score (0.0 to 1.0)
-
-CORRECT Examples (✓ FIRST-PERSON):
-- "I think Alice is more reliable because she consistently delivers on time and writes clean code"
-- "Previously I thought all engineers were equal, but now I feel that experience and track record really matter"
-- "I believe reliability is best measured by consistent output over time"
-- "I've come to believe that track records are more important than potential"
-
-WRONG Examples (✗ THIRD-PERSON - DO NOT USE):
-- "The speaker thinks Alice is more reliable"
-- "They believe reliability matters"
-- "It is believed that Alice is better"
-
-If no genuine opinions are expressed (e.g., the response just says "I don't know"), return an empty list."""
-
-    try:
-        result = await llm_config.call(
-            messages=[
-                {
-                    "role": "system",
-                    "content": "You are converting opinions from text into first-person statements. Always use 'I think', 'I believe', 'I feel', etc. NEVER use third-person like 'The speaker' or 'They'.",
-                },
-                {"role": "user", "content": extraction_prompt},
-            ],
-            response_format=OpinionExtractionResponse,
-            scope="memory_extract_opinion",
-        )
-
-        # Format opinions with confidence score and convert to first-person
-        formatted_opinions = []
-        for op in result.opinions:
-            # Convert third-person to first-person if needed
-            opinion_text = op.opinion
-
-            # Replace common third-person patterns with first-person
-            def singularize_verb(verb):
-                if verb.endswith("es"):
-                    return verb[:-1]  # believes -> believe
-                elif verb.endswith("s"):
-                    return verb[:-1]  # thinks -> think
-                return verb
-
-            # Pattern: "The speaker/user [verb]..." -> "I [verb]..."
-            match = re.match(
-                r"^(The speaker|The user|They|It is believed) (believes?|thinks?|feels?|says|asserts?|considers?)(\s+that)?(.*)$",
-                opinion_text,
-                re.IGNORECASE,
-            )
-            if match:
-                verb = singularize_verb(match.group(2))
-                that_part = match.group(3) or ""  # Keep " that" if present
-                rest = match.group(4)
-                opinion_text = f"I {verb}{that_part}{rest}"
-
-            # If still doesn't start with first-person, prepend "I believe that "
-            first_person_starters = [
-                "I think",
-                "I believe",
-                "I feel",
-                "In my view",
-                "I've come to believe",
-                "Previously I",
-            ]
-            if not any(opinion_text.startswith(starter) for starter in first_person_starters):
-                opinion_text = "I believe that " + opinion_text[0].lower() + opinion_text[1:]
-
-            formatted_opinions.append(Opinion(opinion=opinion_text, confidence=op.confidence))
-
-        return formatted_opinions
-
-    except Exception as e:
-        logger.warning(f"Failed to extract opinions: {str(e)}")
-        return []
+    return f"You are a person with your own thoughts, experiences, opinions, and disposition. When asked a question, respond naturally like a human would - share what you genuinely think based on what you know and have experienced. {disposition_instruction} Be direct, express your views confidently, and use 'I think', 'I believe', 'in my view', etc. Respond in plain text without markdown formatting. IMPORTANT: Detect the language of the question and respond in the SAME language. Do not translate to English if the question is in another language."
 
 
 async def reflect(
@@ -290,7 +196,6 @@ async def reflect(
     query: str,
     experience_facts: list[str] = None,
     world_facts: list[str] = None,
-    opinion_facts: list[str] = None,
     name: str = "Assistant",
     disposition: DispositionTraits = None,
     background: str = "",
@@ -307,7 +212,6 @@ async def reflect(
         query: Question to answer
         experience_facts: List of experience/agent fact strings
         world_facts: List of world fact strings
-        opinion_facts: List of opinion fact strings
         name: Name of the agent/persona
         disposition: Disposition traits (defaults to neutral)
         background: Background information
@@ -328,18 +232,15 @@ async def reflect(
 
     agent_results = to_memory_facts(experience_facts or [], "experience")
     world_results = to_memory_facts(world_facts or [], "world")
-    opinion_results = to_memory_facts(opinion_facts or [], "opinion")
 
     # Format facts for prompt
     agent_facts_text = format_facts_for_prompt(agent_results)
     world_facts_text = format_facts_for_prompt(world_results)
-    opinion_facts_text = format_facts_for_prompt(opinion_results)
 
     # Build prompt
     prompt = build_think_prompt(
         agent_facts_text=agent_facts_text,
         world_facts_text=world_facts_text,
-        opinion_facts_text=opinion_facts_text,
         query=query,
         name=name,
         disposition=disposition,

hindsight-api/hindsight_api/engine/search/trace.py

@@ -11,6 +11,13 @@ from typing import Any, Literal
 from pydantic import BaseModel, Field
 
 
+class TemporalConstraint(BaseModel):
+    """Detected temporal constraint from query analysis."""
+
+    start: datetime | None = Field(default=None, description="Start of temporal range")
+    end: datetime | None = Field(default=None, description="End of temporal range")
+
+
 class QueryInfo(BaseModel):
     """Information about the search query."""
 
@@ -19,6 +26,11 @@ class QueryInfo(BaseModel):
     timestamp: datetime = Field(description="When the query was executed")
     budget: int = Field(description="Maximum nodes to explore")
     max_tokens: int = Field(description="Maximum tokens to return in results")
+    tags: list[str] | None = Field(default=None, description="Tags filter applied to recall")
+    tags_match: str | None = Field(default=None, description="Tags matching mode: any, all, any_strict, all_strict")
+    temporal_constraint: TemporalConstraint | None = Field(
+        default=None, description="Detected temporal range from query"
+    )
 
 
 class EntryPoint(BaseModel):

hindsight-api/hindsight_api/engine/search/tracer.py

@@ -22,6 +22,7 @@ from .trace import (
     SearchPhaseMetrics,
     SearchSummary,
     SearchTrace,
+    TemporalConstraint,
     WeightComponents,
 )
 
@@ -45,7 +46,14 @@ class SearchTracer:
         json_output = trace.to_json()
     """
 
-    def __init__(self, query: str, budget: int, max_tokens: int):
+    def __init__(
+        self,
+        query: str,
+        budget: int,
+        max_tokens: int,
+        tags: list[str] | None = None,
+        tags_match: str | None = None,
+    ):
         """
         Initialize tracer.
 
@@ -53,10 +61,14 @@ class SearchTracer:
             query: Search query text
             budget: Maximum nodes to explore
             max_tokens: Maximum tokens to return in results
+            tags: Tags filter applied to recall
+            tags_match: Tags matching mode (any, all, any_strict, all_strict)
         """
         self.query_text = query
         self.budget = budget
         self.max_tokens = max_tokens
+        self.tags = tags
+        self.tags_match = tags_match
 
         # Trace data
         self.query_embedding: list[float] | None = None
@@ -66,6 +78,9 @@ class SearchTracer:
         self.pruned: list[PruningDecision] = []
         self.phase_metrics: list[SearchPhaseMetrics] = []
 
+        # Temporal constraint detected from query
+        self.temporal_constraint: TemporalConstraint | None = None
+
         # New 4-way retrieval tracking
         self.retrieval_results: list[RetrievalMethodResults] = []
         self.rrf_merged: list[RRFMergeResult] = []
@@ -88,6 +103,11 @@ class SearchTracer:
         """Record the query embedding."""
         self.query_embedding = embedding
 
+    def record_temporal_constraint(self, start: datetime | None, end: datetime | None):
+        """Record the detected temporal constraint from query analysis."""
+        if start is not None or end is not None:
+            self.temporal_constraint = TemporalConstraint(start=start, end=end)
+
     def add_entry_point(self, node_id: str, text: str, similarity: float, rank: int):
         """
         Record an entry point.
@@ -115,7 +135,7 @@ class SearchTracer:
         node_id: str,
         text: str,
         context: str,
-        event_date: datetime,
+        event_date: datetime | None,
         access_count: int,
         is_entry_point: bool,
         parent_node_id: str | None,
@@ -428,6 +448,9 @@ class SearchTracer:
             timestamp=datetime.now(UTC),
             budget=self.budget,
             max_tokens=self.max_tokens,
+            tags=self.tags,
+            tags_match=self.tags_match,
+            temporal_constraint=self.temporal_constraint,
         )
 
         # Create summary

hindsight-api/hindsight_api/engine/search/types.py

@@ -10,6 +10,24 @@ from datetime import datetime
 from typing import Any
 
 
+@dataclass
+class MPFPTimings:
+    """Timing breakdown for a single MPFP retrieval call."""
+
+    fact_type: str
+    edge_count: int = 0  # Total edges loaded
+    db_queries: int = 0  # Number of DB queries for edge loading
+    edge_load_time: float = 0.0  # Time spent loading edges from DB
+    traverse: float = 0.0  # Total traversal time (includes edge loading)
+    pattern_count: int = 0  # Number of patterns executed
+    fusion: float = 0.0  # Time for RRF fusion
+    fetch: float = 0.0  # Time to fetch memory unit details
+    seeds_time: float = 0.0  # Time to find semantic seeds (if fallback used)
+    result_count: int = 0  # Number of results returned
+    # Detailed per-hop timing: list of {hop, exec_time, uncached, load_time, edges_loaded, total_time}
+    hop_details: list[dict] = field(default_factory=list)
+
+
 @dataclass
 class RetrievalResult:
     """
@@ -30,6 +48,7 @@ class RetrievalResult:
     chunk_id: str | None = None
     access_count: int = 0
     embedding: list[float] | None = None
+    tags: list[str] | None = None  # Visibility scope tags
 
     # Retrieval-specific scores (only one will be set depending on retrieval method)
     similarity: float | None = None  # Semantic retrieval
@@ -54,6 +73,7 @@ class RetrievalResult:
             chunk_id=row.get("chunk_id"),
             access_count=row.get("access_count", 0),
             embedding=row.get("embedding"),
+            tags=row.get("tags"),
             similarity=row.get("similarity"),
             bm25_score=row.get("bm25_score"),
             activation=row.get("activation"),
@@ -138,6 +158,7 @@ class ScoredResult:
             "chunk_id": self.retrieval.chunk_id,
             "access_count": self.retrieval.access_count,
             "embedding": self.retrieval.embedding,
+            "tags": self.retrieval.tags,
             "semantic_similarity": self.retrieval.similarity,
             "bm25_score": self.retrieval.bm25_score,
         }

hindsight-api/hindsight_api/engine/task_backend.py

@@ -89,6 +89,61 @@ class TaskBackend(ABC):
             traceback.print_exc()
 
 
+class SyncTaskBackend(TaskBackend):
+    """
+    Synchronous task backend that executes tasks immediately.
+
+    This is useful for embedded/CLI usage where we don't want background
+    workers that prevent clean exit. Tasks are executed inline rather than
+    being queued.
+    """
+
+    async def initialize(self):
+        """No-op for sync backend."""
+        self._initialized = True
+        logger.debug("SyncTaskBackend initialized")
+
+    async def submit_task(self, task_dict: dict[str, Any]):
+        """
+        Execute the task immediately (synchronously).
+
+        Args:
+            task_dict: Task dictionary to execute
+        """
+        if not self._initialized:
+            await self.initialize()
+
+        await self._execute_task(task_dict)
+
+    async def shutdown(self):
+        """No-op for sync backend."""
+        self._initialized = False
+        logger.debug("SyncTaskBackend shutdown")
+
+
+class NoopTaskBackend(TaskBackend):
+    """
+    No-op task backend that discards all tasks.
+
+    This is useful for tests where background task execution is not needed
+    and would only slow down the test suite.
+    """
+
+    async def initialize(self):
+        """No-op."""
+        self._initialized = True
+        logger.debug("NoopTaskBackend initialized")
+
+    async def submit_task(self, task_dict: dict[str, Any]):
+        """Discard the task (do nothing)."""
+        pass
+
+    async def shutdown(self):
+        """No-op."""
+        self._initialized = False
+        logger.debug("NoopTaskBackend shutdown")
+
+
 class AsyncIOQueueBackend(TaskBackend):
     """
     Task backend implementation using asyncio queues.
@@ -97,7 +152,7 @@ class AsyncIOQueueBackend(TaskBackend):
     and a periodic consumer worker.
     """
 
-    def __init__(self, batch_size: int = 100, batch_interval: float = 1.0):
+    def __init__(self, batch_size: int = 10, batch_interval: float = 1.0):
         """
         Initialize AsyncIO queue backend.
 
@@ -111,6 +166,8 @@ class AsyncIOQueueBackend(TaskBackend):
         self._shutdown_event: asyncio.Event | None = None
         self._batch_size = batch_size
         self._batch_interval = batch_interval
+        self._in_flight_count = 0
+        self._in_flight_lock = asyncio.Lock()
 
     async def initialize(self):
         """Initialize the queue and start the worker."""
@@ -134,33 +191,31 @@ class AsyncIOQueueBackend(TaskBackend):
             await self.initialize()
 
         await self._queue.put(task_dict)
-        task_type = task_dict.get("type", "unknown")
-        task_id = task_dict.get("id")
 
-    async def wait_for_pending_tasks(self, timeout: float = 5.0):
+    async def wait_for_pending_tasks(self, timeout: float = 120.0):
         """
-        Wait for all pending tasks in the queue to be processed.
+        Wait for all pending tasks in the queue and in-flight tasks to complete.
 
         This is useful in tests to ensure background tasks complete before assertions.
 
         Args:
-            timeout: Maximum time to wait in seconds
+            timeout: Maximum time to wait in seconds (default 120s for long-running tasks)
         """
         if not self._initialized or self._queue is None:
             return
 
-        # Wait for queue to be empty and give worker time to process
+        # Wait for queue to be empty AND no in-flight tasks
         start_time = asyncio.get_event_loop().time()
         while asyncio.get_event_loop().time() - start_time < timeout:
-            if self._queue.empty():
-                # Queue is empty, give worker a bit more time to finish any in-flight task
-                await asyncio.sleep(0.3)
-                # Check again - if still empty, we're done
-                if self._queue.empty():
-                    return
-            else:
-                # Queue not empty, wait a bit
-                await asyncio.sleep(0.1)
+            async with self._in_flight_lock:
+                in_flight = self._in_flight_count
+
+            if self._queue.empty() and in_flight == 0:
+                # Queue is empty and no tasks in flight, we're done
+                return
+
+            # Wait a bit before checking again
+            await asyncio.sleep(0.5)
 
     async def shutdown(self):
         """Shutdown the worker and drain the queue."""
@@ -183,6 +238,39 @@ class AsyncIOQueueBackend(TaskBackend):
         self._initialized = False
         logger.info("AsyncIOQueueBackend shutdown complete")
 
+    async def _execute_task_with_tracking(self, task_dict: dict[str, Any]):
+        """Execute a task and track its in-flight status."""
+        async with self._in_flight_lock:
+            self._in_flight_count += 1
+        try:
+            await self._execute_task(task_dict)
+        finally:
+            async with self._in_flight_lock:
+                self._in_flight_count -= 1
+
+    async def _execute_task_no_tracking(self, task_dict: dict[str, Any]):
+        """Execute a task without in-flight tracking (tracking done at batch level)."""
+        await self._execute_task(task_dict)
+
+    def _get_queue_stats(self) -> tuple[int, dict[str, int]]:
+        """Get current queue size and bank_id distribution."""
+        queue_size = self._queue.qsize() if self._queue else 0
+        bank_distribution: dict[str, int] = {}
+
+        if queue_size > 0 and self._queue:
+            # Peek at queue items without removing them
+            # Note: This is a snapshot and may not be perfectly accurate due to concurrency
+            try:
+                # Access internal deque for logging purposes only
+                items = list(self._queue._queue)  # type: ignore[attr-defined]
+                for item in items:
+                    bank_id = item.get("bank_id", "unknown")
+                    bank_distribution[bank_id] = bank_distribution.get(bank_id, 0) + 1
+            except Exception:
+                pass  # Queue access failed, return empty distribution
+
+        return queue_size, bank_distribution
+
     async def _worker(self):
         """
         Background worker that processes tasks in batches.
@@ -200,17 +288,52 @@ class AsyncIOQueueBackend(TaskBackend):
                     try:
                         remaining_time = max(0.1, deadline - asyncio.get_event_loop().time())
                         task_dict = await asyncio.wait_for(self._queue.get(), timeout=remaining_time)
+                        # Track task as in-flight immediately when picked up from queue
+                        # This prevents wait_for_pending_tasks from returning too early
+                        async with self._in_flight_lock:
+                            self._in_flight_count += 1
                         tasks.append(task_dict)
                     except TimeoutError:
                         break
 
                 # Process batch
                 if tasks:
-                    # Execute tasks concurrently
+                    # Log batch start with queue stats
+                    queue_size, bank_distribution = self._get_queue_stats()
+
+                    # Summarize batch by task type and bank
+                    batch_summary: dict[str, dict[str, int]] = {}
+                    for task_dict in tasks:
+                        task_type = task_dict.get("type", "unknown")
+                        bank_id = task_dict.get("bank_id", "unknown")
+                        if task_type not in batch_summary:
+                            batch_summary[task_type] = {}
+                        batch_summary[task_type][bank_id] = batch_summary[task_type].get(bank_id, 0) + 1
+
+                    # Build log message
+                    batch_parts = []
+                    for task_type, banks in sorted(batch_summary.items()):
+                        bank_str = ", ".join(f"{b}:{c}" for b, c in sorted(banks.items()))
+                        batch_parts.append(f"{task_type}[{bank_str}]")
+                    batch_str = ", ".join(batch_parts)
+
+                    if queue_size > 0:
+                        pending_str = ", ".join(f"{k}:{v}" for k, v in sorted(bank_distribution.items()))
+                        logger.info(
+                            f"Processing {len(tasks)} tasks: {batch_str} (pending={queue_size} [{pending_str}])"
+                        )
+                    else:
+                        logger.info(f"Processing {len(tasks)} tasks: {batch_str}")
+
+                    # Execute tasks concurrently (in_flight already tracked when picked up)
                     await asyncio.gather(
-                        *[self._execute_task(task_dict) for task_dict in tasks], return_exceptions=True
+                        *[self._execute_task_no_tracking(task_dict) for task_dict in tasks], return_exceptions=True
                     )
 
+                    # Decrement in_flight count after all tasks complete
+                    async with self._in_flight_lock:
+                        self._in_flight_count -= len(tasks)
+
             except asyncio.CancelledError:
                 break
             except Exception as e:

hindsight-api/hindsight_api/engine/utils.py

@@ -49,7 +49,7 @@ async def extract_facts(
     if not text or not text.strip():
         return [], []
 
-    facts, chunks = await extract_facts_from_text(
+    facts, chunks, _ = await extract_facts_from_text(
         text,
         event_date,
         context=context,

hindsight-api/hindsight_api/extensions/__init__.py

@@ -0,0 +1,66 @@
+"""
+Hindsight Extensions System.
+
+Extensions allow customizing and extending Hindsight behavior without modifying core code.
+Extensions are loaded via environment variables pointing to implementation classes.
+
+Example:
+    HINDSIGHT_API_OPERATION_VALIDATOR_EXTENSION=mypackage.validators:MyValidator
+    HINDSIGHT_API_OPERATION_VALIDATOR_MAX_RETRIES=3
+
+    HINDSIGHT_API_HTTP_EXTENSION=mypackage.http:MyHttpExtension
+    HINDSIGHT_API_HTTP_SOME_CONFIG=value
+
+Extensions receive an ExtensionContext that provides a controlled API for interacting
+with the system (e.g., running migrations for tenant schemas).
+"""
+
+from hindsight_api.extensions.base import Extension
+from hindsight_api.extensions.builtin import ApiKeyTenantExtension
+from hindsight_api.extensions.context import DefaultExtensionContext, ExtensionContext
+from hindsight_api.extensions.http import HttpExtension
+from hindsight_api.extensions.loader import load_extension
+from hindsight_api.extensions.operation_validator import (
+    OperationValidationError,
+    OperationValidatorExtension,
+    RecallContext,
+    RecallResult,
+    ReflectContext,
+    ReflectResultContext,
+    RetainContext,
+    RetainResult,
+    ValidationResult,
+)
+from hindsight_api.extensions.tenant import (
+    AuthenticationError,
+    TenantContext,
+    TenantExtension,
+)
+from hindsight_api.models import RequestContext
+
+__all__ = [
+    # Base
+    "Extension",
+    "load_extension",
+    # Context
+    "ExtensionContext",
+    "DefaultExtensionContext",
+    # HTTP Extension
+    "HttpExtension",
+    # Operation Validator
+    "OperationValidationError",
+    "OperationValidatorExtension",
+    "RecallContext",
+    "RecallResult",
+    "ReflectContext",
+    "ReflectResultContext",
+    "RetainContext",
+    "RetainResult",
+    "ValidationResult",
+    # Tenant/Auth
+    "ApiKeyTenantExtension",
+    "AuthenticationError",
+    "RequestContext",
+    "TenantContext",
+    "TenantExtension",
+]

hindsight-api/hindsight_api/extensions/base.py

@@ -0,0 +1,81 @@
+"""Base Extension class for all Hindsight extensions."""
+
+from abc import ABC
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from hindsight_api.extensions.context import ExtensionContext
+
+
+class Extension(ABC):
+    """
+    Base class for all Hindsight extensions.
+
+    Extensions are loaded via environment variables and receive configuration
+    from prefixed environment variables.
+
+    Example:
+        HINDSIGHT_API_MY_EXTENSION=mypackage.ext:MyExtension
+        HINDSIGHT_API_MY_SOME_CONFIG=value
+
+        The extension receives: {"some_config": "value"}
+
+    Extensions also receive an ExtensionContext that provides a controlled API
+    for interacting with the system (e.g., running migrations for tenant schemas).
+    """
+
+    def __init__(self, config: dict[str, str]):
+        """
+        Initialize the extension with configuration.
+
+        Args:
+            config: Dictionary of configuration values from environment variables.
+                    Keys are lowercased with the prefix stripped.
+        """
+        self.config = config
+        self._context: "ExtensionContext | None" = None
+
+    def set_context(self, context: "ExtensionContext") -> None:
+        """
+        Set the extension context.
+
+        Called by the extension loader after instantiation.
+        Extensions should not call this directly.
+
+        Args:
+            context: The ExtensionContext providing system APIs.
+        """
+        self._context = context
+
+    @property
+    def context(self) -> "ExtensionContext":
+        """
+        Get the extension context.
+
+        Returns:
+            The ExtensionContext providing system APIs.
+
+        Raises:
+            RuntimeError: If context has not been set yet.
+        """
+        if self._context is None:
+            raise RuntimeError(
+                "Extension context not set. Context is available after the extension is loaded by the system."
+            )
+        return self._context
+
+    async def on_startup(self) -> None:
+        """
+        Called when the application starts.
+
+        Override to perform initialization tasks like connecting to external services.
+        """
+        pass
+
+    async def on_shutdown(self) -> None:
+        """
+        Called when the application shuts down.
+
+        Override to perform cleanup tasks like closing connections.
+        """
+        pass

hindsight-api/hindsight_api/extensions/builtin/__init__.py

@@ -0,0 +1,18 @@
+"""
+Built-in extension implementations.
+
+These are ready-to-use implementations of the extension interfaces.
+They can be used directly or serve as examples for custom implementations.
+
+Available built-in extensions:
+    - ApiKeyTenantExtension: Simple API key validation with public schema
+
+Example usage:
+    HINDSIGHT_API_TENANT_EXTENSION=hindsight_api.extensions.builtin.tenant:ApiKeyTenantExtension
+"""
+
+from hindsight_api.extensions.builtin.tenant import ApiKeyTenantExtension
+
+__all__ = [
+    "ApiKeyTenantExtension",
+]

hindsight-api/hindsight_api/extensions/builtin/tenant.py

@@ -0,0 +1,33 @@
+"""Built-in tenant extension implementations."""
+
+from hindsight_api.extensions.tenant import AuthenticationError, TenantContext, TenantExtension
+from hindsight_api.models import RequestContext
+
+
+class ApiKeyTenantExtension(TenantExtension):
+    """
+    Built-in tenant extension that validates API key against an environment variable.
+
+    This is a simple implementation that:
+    1. Validates the API key matches HINDSIGHT_API_TENANT_API_KEY
+    2. Returns 'public' as the schema for all authenticated requests
+
+    Configuration:
+        HINDSIGHT_API_TENANT_EXTENSION=hindsight_api.extensions.builtin.tenant:ApiKeyTenantExtension
+        HINDSIGHT_API_TENANT_API_KEY=your-secret-key
+
+    For multi-tenant setups with separate schemas per tenant, implement a custom
+    TenantExtension that looks up the schema based on the API key or token claims.
+    """
+
+    def __init__(self, config: dict[str, str]):
+        super().__init__(config)
+        self.expected_api_key = config.get("api_key")
+        if not self.expected_api_key:
+            raise ValueError("HINDSIGHT_API_TENANT_API_KEY is required when using ApiKeyTenantExtension")
+
+    async def authenticate(self, context: RequestContext) -> TenantContext:
+        """Validate API key and return public schema context."""
+        if context.api_key != self.expected_api_key:
+            raise AuthenticationError("Invalid API key")
+        return TenantContext(schema_name="public")

hindsight-api/hindsight_api/extensions/context.py

@@ -0,0 +1,126 @@
+"""Extension context providing a controlled API for extensions to interact with the system."""
+
+from abc import ABC, abstractmethod
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from hindsight_api.engine.interface import MemoryEngineInterface
+
+
+class ExtensionContext(ABC):
+    """
+    Abstract context providing a controlled API for extensions.
+
+    Extensions receive this context instead of direct access to internal
+    components like MemoryEngine or database connections. This provides:
+    - A stable API that won't break when internals change
+    - Security by limiting what extensions can access
+    - Clear documentation of what extensions can do
+
+    Built-in implementation:
+        hindsight_api.extensions.builtin.context.DefaultExtensionContext
+
+    Example usage in an extension:
+        class MyTenantExtension(TenantExtension):
+            async def on_startup(self) -> None:
+                # Run migrations for a new tenant schema
+                await self.context.run_migration("tenant_acme")
+
+        class MyHttpExtension(HttpExtension):
+            def get_router(self, memory):
+                # Use memory engine for custom endpoints
+                engine = self.context.get_memory_engine()
+                ...
+    """
+
+    @abstractmethod
+    async def run_migration(self, schema: str) -> None:
+        """
+        Run database migrations for a specific schema.
+
+        This creates the schema if it doesn't exist and runs all pending
+        migrations. Uses advisory locks to coordinate between distributed workers.
+
+        Args:
+            schema: PostgreSQL schema name (e.g., "tenant_acme").
+                    The schema will be created if it doesn't exist.
+
+        Raises:
+            RuntimeError: If migrations fail to complete.
+
+        Example:
+            # Provision a new tenant schema
+            await context.run_migration("tenant_acme")
+        """
+        ...
+
+    @abstractmethod
+    def get_memory_engine(self) -> "MemoryEngineInterface":
+        """
+        Get the memory engine interface.
+
+        Returns the MemoryEngineInterface for performing memory operations
+        like retain, recall, reflect, and entity/document management.
+
+        Returns:
+            MemoryEngineInterface instance.
+
+        Example:
+            engine = context.get_memory_engine()
+            result = await engine.recall_async(bank_id, query)
+        """
+        ...
+
+
+class DefaultExtensionContext(ExtensionContext):
+    """
+    Default implementation of ExtensionContext.
+
+    Uses the system's database URL and migration infrastructure.
+    """
+
+    def __init__(
+        self,
+        database_url: str,
+        memory_engine: "MemoryEngineInterface | None" = None,
+    ):
+        """
+        Initialize the context.
+
+        Args:
+            database_url: SQLAlchemy database URL for migrations.
+            memory_engine: Optional MemoryEngine instance for memory operations.
+        """
+        self._database_url = database_url
+        self._memory_engine = memory_engine
+
+    async def run_migration(self, schema: str) -> None:
+        """Run migrations for a specific schema."""
+        from hindsight_api.migrations import ensure_embedding_dimension, run_migrations
+
+        # Prefer getting URL from memory engine (handles pg0 case where URL is set after init)
+        db_url = self._database_url
+        if self._memory_engine is not None:
+            engine_url = getattr(self._memory_engine, "db_url", None)
+            if engine_url:
+                db_url = engine_url
+
+        run_migrations(db_url, schema=schema)
+
+        # Ensure embedding column dimension matches the model's dimension
+        # This is needed because migrations create columns with default dimension
+        if self._memory_engine is not None:
+            embeddings = getattr(self._memory_engine, "embeddings", None)
+            if embeddings is not None:
+                dimension = getattr(embeddings, "dimension", None)
+                if dimension is not None:
+                    ensure_embedding_dimension(db_url, dimension, schema=schema)
+
+    def get_memory_engine(self) -> "MemoryEngineInterface":
+        """Get the memory engine interface."""
+        if self._memory_engine is None:
+            raise RuntimeError(
+                "Memory engine not configured in ExtensionContext. "
+                "Ensure the context was created with a memory_engine parameter."
+            )
+        return self._memory_engine

hindsight-api/hindsight_api/extensions/http.py

@@ -0,0 +1,89 @@
+"""
+HTTP Extension for adding custom endpoints to the Hindsight API.
+
+This extension allows adding custom HTTP endpoints under the /ext/ path prefix.
+The extension provides a FastAPI router that is mounted on the main application.
+"""
+
+from abc import ABC, abstractmethod
+from typing import TYPE_CHECKING
+
+from fastapi import APIRouter
+
+from hindsight_api.extensions.base import Extension
+
+if TYPE_CHECKING:
+    from hindsight_api import MemoryEngine
+
+
+class HttpExtension(Extension, ABC):
+    """
+    Base class for HTTP extensions that add custom API endpoints.
+
+    HTTP extensions provide a FastAPI router that gets mounted under /ext/.
+    The extension has full control over the routes, request/response models, and handlers.
+
+    Example:
+        ```python
+        from fastapi import APIRouter
+        from hindsight_api.extensions import HttpExtension
+
+        class MyHttpExtension(HttpExtension):
+            def get_router(self, memory: MemoryEngine) -> APIRouter:
+                router = APIRouter()
+
+                @router.get("/hello")
+                async def hello():
+                    return {"message": "Hello from extension!"}
+
+                @router.post("/custom/{bank_id}/action")
+                async def custom_action(bank_id: str):
+                    # Access memory engine for database operations
+                    pool = await memory._get_pool()
+                    # ... custom logic
+                    return {"status": "ok"}
+
+                return router
+        ```
+
+    The routes will be available at:
+        - GET /ext/hello
+        - POST /ext/custom/{bank_id}/action
+
+    Configuration via environment variables:
+        HINDSIGHT_API_HTTP_EXTENSION=mypackage.ext:MyHttpExtension
+        HINDSIGHT_API_HTTP_SOME_CONFIG=value
+
+    The extension receives config: {"some_config": "value"}
+    """
+
+    @abstractmethod
+    def get_router(self, memory: "MemoryEngine") -> APIRouter:
+        """
+        Return a FastAPI router with custom endpoints.
+
+        The router will be mounted at /ext/ on the main application.
+        All routes defined in the router will be prefixed with /ext/.
+
+        Args:
+            memory: The MemoryEngine instance for database access and core operations.
+                   Use this to access the connection pool, run queries, or call
+                   memory operations like retain, recall, etc.
+
+        Returns:
+            A FastAPI APIRouter with the custom endpoints defined.
+
+        Example:
+            ```python
+            def get_router(self, memory: MemoryEngine) -> APIRouter:
+                router = APIRouter(tags=["My Extension"])
+
+                @router.get("/status")
+                async def status():
+                    health = await memory.health_check()
+                    return {"extension": "healthy", "memory": health}
+
+                return router
+            ```
+        """
+        pass

hindsight-api/hindsight_api/extensions/loader.py

@@ -0,0 +1,125 @@
+"""Extension loader utilities."""
+
+import importlib
+import logging
+import os
+from typing import TYPE_CHECKING, TypeVar
+
+from hindsight_api.extensions.base import Extension
+
+if TYPE_CHECKING:
+    from hindsight_api.extensions.context import ExtensionContext
+
+logger = logging.getLogger(__name__)
+
+T = TypeVar("T", bound=Extension)
+
+
+class ExtensionLoadError(Exception):
+    """Raised when an extension fails to load."""
+
+    pass
+
+
+def load_extension(
+    prefix: str,
+    base_class: type[T],
+    env_prefix: str = "HINDSIGHT_API",
+    context: "ExtensionContext | None" = None,
+) -> T | None:
+    """
+    Load an extension from environment variable configuration.
+
+    The extension class is specified via {env_prefix}_{prefix}_EXTENSION environment
+    variable in the format "module.path:ClassName".
+
+    Configuration for the extension is collected from all environment variables
+    matching {env_prefix}_{prefix}_* (excluding the EXTENSION variable itself).
+
+    Args:
+        prefix: The extension prefix (e.g., "OPERATION_VALIDATOR").
+        base_class: The base class that the extension must inherit from.
+        env_prefix: The environment variable prefix (default: "HINDSIGHT_API").
+        context: Optional ExtensionContext to provide system APIs to the extension.
+
+    Returns:
+        An instance of the extension, or None if not configured.
+
+    Raises:
+        ExtensionLoadError: If the extension fails to load or validate.
+
+    Example:
+        HINDSIGHT_API_OPERATION_VALIDATOR_EXTENSION=mypackage.validators:MyValidator
+        HINDSIGHT_API_OPERATION_VALIDATOR_MAX_REQUESTS=100
+
+        ext = load_extension("OPERATION_VALIDATOR", OperationValidatorExtension)
+        # ext.config == {"max_requests": "100"}
+    """
+    env_var = f"{env_prefix}_{prefix}_EXTENSION"
+    ext_path = os.getenv(env_var)
+
+    if not ext_path:
+        logger.debug(f"No extension configured for {env_var}")
+        return None
+
+    logger.info(f"Loading extension from {env_var}={ext_path}")
+
+    # Parse "module.path:ClassName"
+    if ":" not in ext_path:
+        raise ExtensionLoadError(f"Invalid extension path '{ext_path}'. Expected format: 'module.path:ClassName'")
+
+    module_path, class_name = ext_path.rsplit(":", 1)
+
+    # Import the module
+    try:
+        module = importlib.import_module(module_path)
+    except ImportError as e:
+        raise ExtensionLoadError(f"Failed to import extension module '{module_path}': {e}") from e
+
+    # Get the class
+    try:
+        ext_class = getattr(module, class_name)
+    except AttributeError as e:
+        raise ExtensionLoadError(f"Extension class '{class_name}' not found in module '{module_path}'") from e
+
+    # Validate inheritance
+    if not isinstance(ext_class, type) or not issubclass(ext_class, base_class):
+        raise ExtensionLoadError(f"Extension class '{ext_class.__name__}' must inherit from '{base_class.__name__}'")
+
+    # Collect configuration from environment variables
+    config = _collect_config(env_prefix, prefix)
+
+    logger.info(f"Loaded extension {ext_class.__name__} with config keys: {list(config.keys())}")
+
+    # Instantiate the extension
+    try:
+        extension = ext_class(config)
+    except Exception as e:
+        raise ExtensionLoadError(f"Failed to instantiate extension '{ext_class.__name__}': {e}") from e
+
+    # Set the context if provided
+    if context is not None:
+        extension.set_context(context)
+        logger.debug(f"Set context on extension {ext_class.__name__}")
+
+    return extension
+
+
+def _collect_config(env_prefix: str, prefix: str) -> dict[str, str]:
+    """
+    Collect configuration from environment variables.
+
+    Collects all variables matching {env_prefix}_{prefix}_* except for
+    {env_prefix}_{prefix}_EXTENSION, strips the prefix, and lowercases keys.
+    """
+    config = {}
+    full_prefix = f"{env_prefix}_{prefix}_"
+    extension_var = f"{full_prefix}EXTENSION"
+
+    for key, value in os.environ.items():
+        if key.startswith(full_prefix) and key != extension_var:
+            # Strip prefix and lowercase the key
+            config_key = key[len(full_prefix) :].lower()
+            config[config_key] = value
+
+    return config

hindsight-api/hindsight_api/extensions/operation_validator.py

@@ -0,0 +1,327 @@
+"""Operation Validator Extension for validating retain/recall/reflect operations."""
+
+from abc import ABC, abstractmethod
+from dataclasses import dataclass, field
+from datetime import datetime
+from typing import TYPE_CHECKING, Any
+
+from hindsight_api.extensions.base import Extension
+
+if TYPE_CHECKING:
+    from hindsight_api.engine.memory_engine import Budget
+    from hindsight_api.engine.response_models import RecallResult as RecallResultModel
+    from hindsight_api.engine.response_models import ReflectResult
+    from hindsight_api.models import RequestContext
+
+
+class OperationValidationError(Exception):
+    """Raised when an operation fails validation."""
+
+    def __init__(self, reason: str, status_code: int = 403):
+        self.reason = reason
+        self.status_code = status_code
+        super().__init__(f"Operation validation failed: {reason}")
+
+
+@dataclass
+class ValidationResult:
+    """Result of an operation validation."""
+
+    allowed: bool
+    reason: str | None = None
+    status_code: int = 403  # Default to Forbidden
+
+    @classmethod
+    def accept(cls) -> "ValidationResult":
+        """Create an accepted validation result."""
+        return cls(allowed=True)
+
+    @classmethod
+    def reject(cls, reason: str, status_code: int = 403) -> "ValidationResult":
+        """Create a rejected validation result with a reason and HTTP status code."""
+        return cls(allowed=False, reason=reason, status_code=status_code)
+
+
+# =============================================================================
+# Pre-operation Contexts (all user-provided parameters)
+# =============================================================================
+
+
+@dataclass
+class RetainContext:
+    """Context for a retain operation validation (pre-operation).
+
+    Contains ALL user-provided parameters for the retain operation.
+    """
+
+    bank_id: str
+    contents: list[dict]  # List of {content, context, event_date, document_id}
+    request_context: "RequestContext"
+    document_id: str | None = None
+    fact_type_override: str | None = None
+    confidence_score: float | None = None
+
+
+@dataclass
+class RecallContext:
+    """Context for a recall operation validation (pre-operation).
+
+    Contains ALL user-provided parameters for the recall operation.
+    """
+
+    bank_id: str
+    query: str
+    request_context: "RequestContext"
+    budget: "Budget | None" = None
+    max_tokens: int = 4096
+    enable_trace: bool = False
+    fact_types: list[str] = field(default_factory=list)
+    question_date: datetime | None = None
+    include_entities: bool = False
+    max_entity_tokens: int = 500
+    include_chunks: bool = False
+    max_chunk_tokens: int = 8192
+
+
+@dataclass
+class ReflectContext:
+    """Context for a reflect operation validation (pre-operation).
+
+    Contains ALL user-provided parameters for the reflect operation.
+    """
+
+    bank_id: str
+    query: str
+    request_context: "RequestContext"
+    budget: "Budget | None" = None
+    context: str | None = None
+
+
+# =============================================================================
+# Post-operation Contexts (includes results)
+# =============================================================================
+
+
+@dataclass
+class RetainResult:
+    """Result context for post-retain hook.
+
+    Contains the operation parameters and the result.
+    """
+
+    bank_id: str
+    contents: list[dict]
+    request_context: "RequestContext"
+    document_id: str | None
+    fact_type_override: str | None
+    confidence_score: float | None
+    # Result
+    unit_ids: list[list[str]]  # List of unit IDs per content item
+    success: bool = True
+    error: str | None = None
+
+
+@dataclass
+class RecallResult:
+    """Result context for post-recall hook.
+
+    Contains the operation parameters and the result.
+    """
+
+    bank_id: str
+    query: str
+    request_context: "RequestContext"
+    budget: "Budget | None"
+    max_tokens: int
+    enable_trace: bool
+    fact_types: list[str]
+    question_date: datetime | None
+    include_entities: bool
+    max_entity_tokens: int
+    include_chunks: bool
+    max_chunk_tokens: int
+    # Result
+    result: "RecallResultModel | None" = None
+    success: bool = True
+    error: str | None = None
+
+
+@dataclass
+class ReflectResultContext:
+    """Result context for post-reflect hook.
+
+    Contains the operation parameters and the result.
+    """
+
+    bank_id: str
+    query: str
+    request_context: "RequestContext"
+    budget: "Budget | None"
+    context: str | None
+    # Result
+    result: "ReflectResult | None" = None
+    success: bool = True
+    error: str | None = None
+
+
+class OperationValidatorExtension(Extension, ABC):
+    """
+    Validates and hooks into retain/recall/reflect operations.
+
+    This extension allows implementing custom logic such as:
+    - Rate limiting (pre-operation)
+    - Quota enforcement (pre-operation)
+    - Permission checks (pre-operation)
+    - Content filtering (pre-operation)
+    - Usage tracking (post-operation)
+    - Audit logging (post-operation)
+    - Metrics collection (post-operation)
+
+    Enable via environment variable:
+        HINDSIGHT_API_OPERATION_VALIDATOR_EXTENSION=mypackage.validators:MyValidator
+
+    Configuration is passed from prefixed environment variables:
+        HINDSIGHT_API_OPERATION_VALIDATOR_MAX_REQUESTS=100
+        -> config = {"max_requests": "100"}
+
+    Hook execution order:
+        1. validate_retain/validate_recall/validate_reflect (pre-operation)
+        2. [operation executes]
+        3. on_retain_complete/on_recall_complete/on_reflect_complete (post-operation)
+    """
+
+    # =========================================================================
+    # Pre-operation validation hooks (abstract - must be implemented)
+    # =========================================================================
+
+    @abstractmethod
+    async def validate_retain(self, ctx: RetainContext) -> ValidationResult:
+        """
+        Validate a retain operation before execution.
+
+        Called before the retain operation is processed. Return ValidationResult.reject()
+        to prevent the operation from executing.
+
+        Args:
+            ctx: Context containing all user-provided parameters:
+                - bank_id: Bank identifier
+                - contents: List of content dicts
+                - request_context: Request context with auth info
+                - document_id: Optional document ID
+                - fact_type_override: Optional fact type override
+                - confidence_score: Optional confidence score
+
+        Returns:
+            ValidationResult indicating whether the operation is allowed.
+        """
+        ...
+
+    @abstractmethod
+    async def validate_recall(self, ctx: RecallContext) -> ValidationResult:
+        """
+        Validate a recall operation before execution.
+
+        Called before the recall operation is processed. Return ValidationResult.reject()
+        to prevent the operation from executing.
+
+        Args:
+            ctx: Context containing all user-provided parameters:
+                - bank_id: Bank identifier
+                - query: Search query
+                - request_context: Request context with auth info
+                - budget: Budget level
+                - max_tokens: Maximum tokens to return
+                - enable_trace: Whether to include trace info
+                - fact_types: List of fact types to search
+                - question_date: Optional date context for query
+                - include_entities: Whether to include entity data
+                - max_entity_tokens: Max tokens for entities
+                - include_chunks: Whether to include chunks
+                - max_chunk_tokens: Max tokens for chunks
+
+        Returns:
+            ValidationResult indicating whether the operation is allowed.
+        """
+        ...
+
+    @abstractmethod
+    async def validate_reflect(self, ctx: ReflectContext) -> ValidationResult:
+        """
+        Validate a reflect operation before execution.
+
+        Called before the reflect operation is processed. Return ValidationResult.reject()
+        to prevent the operation from executing.
+
+        Args:
+            ctx: Context containing all user-provided parameters:
+                - bank_id: Bank identifier
+                - query: Question to answer
+                - request_context: Request context with auth info
+                - budget: Budget level
+                - context: Optional additional context
+
+        Returns:
+            ValidationResult indicating whether the operation is allowed.
+        """
+        ...
+
+    # =========================================================================
+    # Post-operation hooks (optional - override to implement)
+    # =========================================================================
+
+    async def on_retain_complete(self, result: RetainResult) -> None:
+        """
+        Called after a retain operation completes (success or failure).
+
+        Override this method to implement post-operation logic such as:
+        - Usage tracking
+        - Audit logging
+        - Metrics collection
+        - Notifications
+
+        Args:
+            result: Result context containing:
+                - All original operation parameters
+                - unit_ids: List of created unit IDs (if success)
+                - success: Whether the operation succeeded
+                - error: Error message (if failed)
+        """
+        pass
+
+    async def on_recall_complete(self, result: RecallResult) -> None:
+        """
+        Called after a recall operation completes (success or failure).
+
+        Override this method to implement post-operation logic such as:
+        - Usage tracking
+        - Audit logging
+        - Metrics collection
+        - Query analytics
+
+        Args:
+            result: Result context containing:
+                - All original operation parameters
+                - result: RecallResultModel (if success)
+                - success: Whether the operation succeeded
+                - error: Error message (if failed)
+        """
+        pass
+
+    async def on_reflect_complete(self, result: ReflectResultContext) -> None:
+        """
+        Called after a reflect operation completes (success or failure).
+
+        Override this method to implement post-operation logic such as:
+        - Usage tracking
+        - Audit logging
+        - Metrics collection
+        - Response analytics
+
+        Args:
+            result: Result context containing:
+                - All original operation parameters
+                - result: ReflectResult (if success)
+                - success: Whether the operation succeeded
+                - error: Error message (if failed)
+        """
+        pass

hindsight-api/hindsight_api/extensions/tenant.py

@@ -0,0 +1,63 @@
+"""Tenant Extension for multi-tenancy and API key authentication."""
+
+from abc import ABC, abstractmethod
+from dataclasses import dataclass
+
+from hindsight_api.extensions.base import Extension
+from hindsight_api.models import RequestContext
+
+
+class AuthenticationError(Exception):
+    """Raised when authentication fails."""
+
+    def __init__(self, reason: str):
+        self.reason = reason
+        super().__init__(f"Authentication failed: {reason}")
+
+
+@dataclass
+class TenantContext:
+    """
+    Tenant context returned by authentication.
+
+    Contains the PostgreSQL schema name for tenant isolation.
+    All database queries will use fully-qualified table names
+    with this schema (e.g., schema_name.memory_units).
+    """
+
+    schema_name: str
+
+
+class TenantExtension(Extension, ABC):
+    """
+    Extension for multi-tenancy and API key authentication.
+
+    This extension validates incoming requests and returns the tenant context
+    including the PostgreSQL schema to use for database operations.
+
+    Built-in implementation:
+        hindsight_api.extensions.builtin.tenant.ApiKeyTenantExtension
+
+    Enable via environment variable:
+        HINDSIGHT_API_TENANT_EXTENSION=hindsight_api.extensions.builtin.tenant:ApiKeyTenantExtension
+        HINDSIGHT_API_TENANT_API_KEY=your-secret-key
+
+    The returned schema_name is used for fully-qualified table names in queries,
+    enabling tenant isolation at the database level.
+    """
+
+    @abstractmethod
+    async def authenticate(self, context: RequestContext) -> TenantContext:
+        """
+        Authenticate the action context and return tenant context.
+
+        Args:
+            context: The action context containing API key and other auth data.
+
+        Returns:
+            TenantContext with the schema_name for database operations.
+
+        Raises:
+            AuthenticationError: If authentication fails.
+        """
+        ...

hindsight-api/hindsight_api/main.py

@@ -4,6 +4,9 @@ Command-line interface for Hindsight API.
 Run the server with:
     hindsight-api
 
+Run as background daemon:
+    hindsight-api --daemon
+
 Stop with Ctrl+C.
 """
 
@@ -20,10 +23,15 @@ import uvicorn
 from . import MemoryEngine
 from .api import create_app
 from .banner import print_banner
-from .config import HindsightConfig, get_config
-
-print()
-print_banner()
+from .config import DEFAULT_WORKERS, ENV_WORKERS, HindsightConfig, get_config
+from .daemon import (
+    DEFAULT_DAEMON_PORT,
+    DEFAULT_IDLE_TIMEOUT,
+    DaemonLock,
+    IdleTimeoutMiddleware,
+    daemonize,
+)
+from .extensions import DefaultExtensionContext, OperationValidatorExtension, TenantExtension, load_extension
 
 # Filter deprecation warnings from third-party libraries
 warnings.filterwarnings("ignore", message="websockets.legacy is deprecated")
@@ -87,7 +95,12 @@ def main():
 
     # Development options
     parser.add_argument("--reload", action="store_true", help="Enable auto-reload on code changes (development only)")
-    parser.add_argument("--workers", type=int, default=1, help="Number of worker processes (default: 1)")
+    parser.add_argument(
+        "--workers",
+        type=int,
+        default=int(os.getenv(ENV_WORKERS, str(DEFAULT_WORKERS))),
+        help=f"Number of worker processes (env: {ENV_WORKERS}, default: {DEFAULT_WORKERS})",
+    )
 
     # Access log options
     parser.add_argument("--access-log", action="store_true", help="Enable access log")
@@ -106,8 +119,52 @@ def main():
     parser.add_argument("--ssl-keyfile", default=None, help="SSL key file")
     parser.add_argument("--ssl-certfile", default=None, help="SSL certificate file")
 
+    # Daemon mode options
+    parser.add_argument(
+        "--daemon",
+        action="store_true",
+        help=f"Run as background daemon (uses port {DEFAULT_DAEMON_PORT}, auto-exits after idle)",
+    )
+    parser.add_argument(
+        "--idle-timeout",
+        type=int,
+        default=DEFAULT_IDLE_TIMEOUT,
+        help=f"Idle timeout in seconds before auto-exit in daemon mode (default: {DEFAULT_IDLE_TIMEOUT})",
+    )
+
     args = parser.parse_args()
 
+    # Daemon mode handling
+    if args.daemon:
+        # Use fixed daemon port
+        args.port = DEFAULT_DAEMON_PORT
+        args.host = "127.0.0.1"  # Only bind to localhost for security
+
+        # Check if another daemon is already running
+        daemon_lock = DaemonLock()
+        if not daemon_lock.acquire():
+            print(f"Daemon already running (PID: {daemon_lock.get_pid()})", file=sys.stderr)
+            sys.exit(1)
+
+        # Fork into background
+        daemonize()
+
+        # Re-acquire lock in child process
+        daemon_lock = DaemonLock()
+        if not daemon_lock.acquire():
+            sys.exit(1)
+
+        # Register cleanup to release lock
+        def release_lock():
+            daemon_lock.release()
+
+        atexit.register(release_lock)
+
+    # Print banner (not in daemon mode)
+    if not args.daemon:
+        print()
+        print_banner()
+
     # Configure Python logging based on log level
     # Update config with CLI override if provided
     if args.log_level != config.log_level:
@@ -117,28 +174,94 @@ def main():
             llm_api_key=config.llm_api_key,
             llm_model=config.llm_model,
             llm_base_url=config.llm_base_url,
+            llm_max_concurrent=config.llm_max_concurrent,
+            llm_timeout=config.llm_timeout,
+            retain_llm_provider=config.retain_llm_provider,
+            retain_llm_api_key=config.retain_llm_api_key,
+            retain_llm_model=config.retain_llm_model,
+            retain_llm_base_url=config.retain_llm_base_url,
+            reflect_llm_provider=config.reflect_llm_provider,
+            reflect_llm_api_key=config.reflect_llm_api_key,
+            reflect_llm_model=config.reflect_llm_model,
+            reflect_llm_base_url=config.reflect_llm_base_url,
             embeddings_provider=config.embeddings_provider,
             embeddings_local_model=config.embeddings_local_model,
             embeddings_tei_url=config.embeddings_tei_url,
+            embeddings_openai_base_url=config.embeddings_openai_base_url,
+            embeddings_cohere_base_url=config.embeddings_cohere_base_url,
             reranker_provider=config.reranker_provider,
             reranker_local_model=config.reranker_local_model,
             reranker_tei_url=config.reranker_tei_url,
+            reranker_tei_batch_size=config.reranker_tei_batch_size,
+            reranker_tei_max_concurrent=config.reranker_tei_max_concurrent,
+            reranker_max_candidates=config.reranker_max_candidates,
+            reranker_cohere_base_url=config.reranker_cohere_base_url,
             host=args.host,
             port=args.port,
             log_level=args.log_level,
             mcp_enabled=config.mcp_enabled,
             graph_retriever=config.graph_retriever,
+            mpfp_top_k_neighbors=config.mpfp_top_k_neighbors,
+            recall_max_concurrent=config.recall_max_concurrent,
+            recall_connection_budget=config.recall_connection_budget,
+            observation_min_facts=config.observation_min_facts,
+            observation_top_entities=config.observation_top_entities,
+            retain_max_completion_tokens=config.retain_max_completion_tokens,
+            retain_chunk_size=config.retain_chunk_size,
+            retain_extract_causal_links=config.retain_extract_causal_links,
+            retain_extraction_mode=config.retain_extraction_mode,
+            retain_observations_async=config.retain_observations_async,
+            skip_llm_verification=config.skip_llm_verification,
+            lazy_reranker=config.lazy_reranker,
+            run_migrations_on_startup=config.run_migrations_on_startup,
+            db_pool_min_size=config.db_pool_min_size,
+            db_pool_max_size=config.db_pool_max_size,
+            db_command_timeout=config.db_command_timeout,
+            db_acquire_timeout=config.db_acquire_timeout,
+            task_backend=config.task_backend,
+            task_backend_memory_batch_size=config.task_backend_memory_batch_size,
+            task_backend_memory_batch_interval=config.task_backend_memory_batch_interval,
+            reflect_max_iterations=config.reflect_max_iterations,
+            mental_model_refresh_concurrency=config.mental_model_refresh_concurrency,
         )
     config.configure_logging()
-    config.log_config()
+    if not args.daemon:
+        config.log_config()
 
     # Register cleanup handlers
     atexit.register(_cleanup)
     signal.signal(signal.SIGINT, _signal_handler)
     signal.signal(signal.SIGTERM, _signal_handler)
 
+    # Load operation validator extension if configured
+    operation_validator = load_extension("OPERATION_VALIDATOR", OperationValidatorExtension)
+    if operation_validator:
+        import logging
+
+        logging.info(f"Loaded operation validator: {operation_validator.__class__.__name__}")
+
+    # Load tenant extension if configured
+    tenant_extension = load_extension("TENANT", TenantExtension)
+    if tenant_extension:
+        import logging
+
+        logging.info(f"Loaded tenant extension: {tenant_extension.__class__.__name__}")
+
     # Create MemoryEngine (reads configuration from environment)
-    _memory = MemoryEngine()
+    _memory = MemoryEngine(
+        operation_validator=operation_validator,
+        tenant_extension=tenant_extension,
+        run_migrations=config.run_migrations_on_startup,
+    )
+
+    # Set extension context on tenant extension (needed for schema provisioning)
+    if tenant_extension:
+        extension_context = DefaultExtensionContext(
+            database_url=config.database_url,
+            memory_engine=_memory,
+        )
+        tenant_extension.set_context(extension_context)
+        logging.info("Extension context set on tenant extension")
 
     # Create FastAPI app
     app = create_app(
@@ -149,15 +272,34 @@ def main():
         initialize_memory=True,
     )
 
+    # Wrap with idle timeout middleware in daemon mode
+    idle_middleware = None
+    if args.daemon:
+        idle_middleware = IdleTimeoutMiddleware(app, idle_timeout=args.idle_timeout)
+        app = idle_middleware
+
     # Prepare uvicorn config
+    # When using workers or reload, we must use import string so each worker can import the app
+    use_import_string = args.workers > 1 or args.reload
+    # Check for uvloop availability
+    try:
+        import uvloop  # noqa: F401
+
+        loop_impl = "uvloop"
+        print("uvloop available, will use for event loop")
+    except ImportError:
+        loop_impl = "asyncio"
+        print("uvloop not installed, using default asyncio event loop")
+
     uvicorn_config = {
-        "app": app,
+        "app": "hindsight_api.server:app" if use_import_string else app,
         "host": args.host,
         "port": args.port,
         "log_level": args.log_level,
         "access_log": args.access_log,
         "proxy_headers": args.proxy_headers,
         "ws": "wsproto",  # Use wsproto instead of websockets to avoid deprecation warnings
+        "loop": loop_impl,  # Explicitly set event loop implementation
     }
 
     # Add optional parameters if provided
@@ -172,20 +314,40 @@ def main():
     if args.ssl_certfile:
         uvicorn_config["ssl_certfile"] = args.ssl_certfile
 
-    from .banner import print_startup_info
+    # Print startup info (not in daemon mode)
+    if not args.daemon:
+        from .banner import print_startup_info
 
-    print_startup_info(
-        host=args.host,
-        port=args.port,
-        database_url=config.database_url,
-        llm_provider=config.llm_provider,
-        llm_model=config.llm_model,
-        embeddings_provider=config.embeddings_provider,
-        reranker_provider=config.reranker_provider,
-        mcp_enabled=config.mcp_enabled,
-    )
+        print_startup_info(
+            host=args.host,
+            port=args.port,
+            database_url=config.database_url,
+            llm_provider=config.llm_provider,
+            llm_model=config.llm_model,
+            embeddings_provider=config.embeddings_provider,
+            reranker_provider=config.reranker_provider,
+            mcp_enabled=config.mcp_enabled,
+        )
 
-    uvicorn.run(**uvicorn_config)
+    # Start idle checker in daemon mode
+    if idle_middleware is not None:
+        # Start the idle checker in a background thread with its own event loop
+        import threading
+
+        def run_idle_checker():
+            import time
+
+            time.sleep(2)  # Wait for uvicorn to start
+            try:
+                loop = asyncio.new_event_loop()
+                asyncio.set_event_loop(loop)
+                loop.run_until_complete(idle_middleware._check_idle())
+            except Exception:
+                pass
+
+        threading.Thread(target=run_idle_checker, daemon=True).start()
+
+    uvicorn.run(**uvicorn_config)  # type: ignore[invalid-argument-type] - dict kwargs
 
 
 if __name__ == "__main__":

hindsight-api/hindsight_api/mcp_local.py

@@ -87,6 +87,7 @@ def create_local_mcp_server(bank_id: str, memory=None) -> FastMCP:
     from hindsight_api import MemoryEngine
     from hindsight_api.engine.memory_engine import Budget
     from hindsight_api.engine.response_models import VALID_RECALL_FACT_TYPES
+    from hindsight_api.models import RequestContext
 
     # Create memory engine with pg0 embedded database if not provided
     if memory is None:
@@ -115,7 +116,11 @@ def create_local_mcp_server(bank_id: str, memory=None) -> FastMCP:
 
         async def _retain():
             try:
-                await memory.retain_batch_async(bank_id=bank_id, contents=[{"content": content, "context": context}])
+                await memory.retain_batch_async(
+                    bank_id=bank_id,
+                    contents=[{"content": content, "context": context}],
+                    request_context=RequestContext(),
+                )
             except Exception as e:
                 logger.error(f"Error storing memory: {e}", exc_info=True)
 
@@ -142,6 +147,7 @@ def create_local_mcp_server(bank_id: str, memory=None) -> FastMCP:
                 fact_type=list(VALID_RECALL_FACT_TYPES),
                 budget=budget_enum,
                 max_tokens=max_tokens,
+                request_context=RequestContext(),
             )
 
             return search_result.model_dump()

hindsight-api/hindsight_api/metrics.py

@@ -5,17 +5,86 @@ This module provides metrics for:
 - Operation latency (retain, recall, reflect) with percentiles
 - Token usage (input/output) per operation
 - Per-bank granularity via labels
+- LLM call latency and token usage with scope dimension
+- HTTP request metrics (latency, count by endpoint/method/status)
+- Process metrics (CPU, memory, file descriptors, threads)
+- Database connection pool metrics
 """
 
 import logging
+import os
+import resource
+import threading
 import time
 from contextlib import contextmanager
+from typing import TYPE_CHECKING, Callable
 
 from opentelemetry import metrics
 from opentelemetry.exporter.prometheus import PrometheusMetricReader
 from opentelemetry.sdk.metrics import MeterProvider
+from opentelemetry.sdk.metrics.view import ExplicitBucketHistogramAggregation, View
 from opentelemetry.sdk.resources import Resource
 
+if TYPE_CHECKING:
+    import asyncpg
+
+
+def _get_tenant() -> str:
+    """Get current tenant (schema) from context for metrics labeling."""
+    # Import here to avoid circular imports
+    from hindsight_api.engine.memory_engine import get_current_schema
+
+    return get_current_schema()
+
+
+# Custom bucket boundaries for operation duration (in seconds)
+# Fine granularity in 0-30s range where most operations complete
+DURATION_BUCKETS = (0.1, 0.25, 0.5, 0.75, 1.0, 2.0, 3.0, 5.0, 7.5, 10.0, 15.0, 20.0, 30.0, 60.0, 120.0)
+
+# LLM duration buckets (finer granularity for faster LLM calls)
+LLM_DURATION_BUCKETS = (0.1, 0.25, 0.5, 1.0, 2.0, 3.0, 5.0, 10.0, 15.0, 30.0, 60.0, 120.0)
+
+# HTTP request duration buckets (millisecond-level for fast endpoints)
+HTTP_DURATION_BUCKETS = (0.005, 0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1.0, 2.5, 5.0, 10.0, 30.0)
+
+
+def get_token_bucket(token_count: int) -> str:
+    """
+    Convert a token count to a bucket label for use as a dimension.
+
+    This allows analyzing token usage patterns without high-cardinality issues.
+
+    Buckets:
+    - "0-100": Very small requests/responses
+    - "100-500": Small requests/responses
+    - "500-1k": Medium requests/responses
+    - "1k-5k": Large requests/responses
+    - "5k-10k": Very large requests/responses
+    - "10k-50k": Huge requests/responses
+    - "50k+": Extremely large requests/responses
+
+    Args:
+        token_count: Number of tokens
+
+    Returns:
+        Bucket label string
+    """
+    if token_count < 100:
+        return "0-100"
+    elif token_count < 500:
+        return "100-500"
+    elif token_count < 1000:
+        return "500-1k"
+    elif token_count < 5000:
+        return "1k-5k"
+    elif token_count < 10000:
+        return "5k-10k"
+    elif token_count < 50000:
+        return "10k-50k"
+    else:
+        return "50k+"
+
+
 logger = logging.getLogger(__name__)
 
 # Global meter instance
@@ -48,8 +117,30 @@ def initialize_metrics(service_name: str = "hindsight-api", service_version: str
     # Create Prometheus metric reader
     prometheus_reader = PrometheusMetricReader()
 
-    # Create meter provider with Prometheus exporter
-    provider = MeterProvider(resource=resource, metric_readers=[prometheus_reader])
+    # Create view with custom bucket boundaries for duration histogram
+    duration_view = View(
+        instrument_name="hindsight.operation.duration",
+        aggregation=ExplicitBucketHistogramAggregation(boundaries=DURATION_BUCKETS),
+    )
+
+    # Create view with custom bucket boundaries for LLM duration histogram
+    llm_duration_view = View(
+        instrument_name="hindsight.llm.duration",
+        aggregation=ExplicitBucketHistogramAggregation(boundaries=LLM_DURATION_BUCKETS),
+    )
+
+    # Create view with custom bucket boundaries for HTTP request duration histogram
+    http_duration_view = View(
+        instrument_name="hindsight.http.duration",
+        aggregation=ExplicitBucketHistogramAggregation(boundaries=HTTP_DURATION_BUCKETS),
+    )
+
+    # Create meter provider with Prometheus exporter and custom views
+    provider = MeterProvider(
+        resource=resource,
+        metric_readers=[prometheus_reader],
+        views=[duration_view, llm_duration_view, http_duration_view],
+    )
 
     # Set the global meter provider
     metrics.set_meter_provider(provider)
@@ -71,43 +162,84 @@ class MetricsCollectorBase:
     """Base class for metrics collectors."""
 
     @contextmanager
-    def record_operation(self, operation: str, bank_id: str, budget: str | None = None, max_tokens: int | None = None):
-        """Context manager to record operation duration and status."""
-        raise NotImplementedError
-
-    def record_tokens(
+    def record_operation(
         self,
         operation: str,
         bank_id: str,
-        input_tokens: int = 0,
-        output_tokens: int = 0,
+        source: str = "api",
         budget: str | None = None,
         max_tokens: int | None = None,
     ):
-        """Record token usage for an operation."""
+        """Context manager to record operation duration and status."""
         raise NotImplementedError
 
+    def record_llm_call(
+        self,
+        provider: str,
+        model: str,
+        scope: str,
+        duration: float,
+        input_tokens: int = 0,
+        output_tokens: int = 0,
+        success: bool = True,
+    ):
+        """
+        Record metrics for an LLM call.
+
+        Args:
+            provider: LLM provider name (openai, anthropic, gemini, groq, ollama, lmstudio)
+            model: Model name
+            scope: Scope identifier (e.g., "memory", "reflect", "entity_observation")
+            duration: Call duration in seconds
+            input_tokens: Number of input/prompt tokens
+            output_tokens: Number of output/completion tokens
+            success: Whether the call was successful
+        """
+        raise NotImplementedError
+
+    @contextmanager
+    def record_http_request(self, method: str, endpoint: str, status_code_getter: Callable[[], int]):
+        """Context manager to record HTTP request metrics."""
+        raise NotImplementedError
+
+    def set_db_pool(self, pool: "asyncpg.Pool"):
+        """Set the database pool for metrics collection."""
+        pass
+
 
 class NoOpMetricsCollector(MetricsCollectorBase):
     """No-op metrics collector that does nothing. Used when metrics are disabled."""
 
     @contextmanager
-    def record_operation(self, operation: str, bank_id: str, budget: str | None = None, max_tokens: int | None = None):
-        """No-op context manager."""
-        yield
-
-    def record_tokens(
+    def record_operation(
         self,
         operation: str,
         bank_id: str,
-        input_tokens: int = 0,
-        output_tokens: int = 0,
+        source: str = "api",
         budget: str | None = None,
         max_tokens: int | None = None,
     ):
-        """No-op token recording."""
+        """No-op context manager."""
+        yield
+
+    def record_llm_call(
+        self,
+        provider: str,
+        model: str,
+        scope: str,
+        duration: float,
+        input_tokens: int = 0,
+        output_tokens: int = 0,
+        success: bool = True,
+    ):
+        """No-op LLM call recording."""
         pass
 
+    @contextmanager
+    def record_http_request(self, method: str, endpoint: str, status_code_getter: Callable[[], int]):
+        """No-op HTTP request recording."""
+        yield
+
 
 class MetricsCollector(MetricsCollectorBase):
     """
@@ -125,33 +257,73 @@ class MetricsCollector(MetricsCollectorBase):
             name="hindsight.operation.duration", description="Duration of Hindsight operations in seconds", unit="s"
         )
 
-        # Token usage counters
-        self.tokens_input = self.meter.create_counter(
-            name="hindsight.tokens.input", description="Number of input tokens consumed", unit="tokens"
-        )
-
-        self.tokens_output = self.meter.create_counter(
-            name="hindsight.tokens.output", description="Number of output tokens generated", unit="tokens"
-        )
-
         # Operation counter (success/failure)
         self.operation_total = self.meter.create_counter(
             name="hindsight.operation.total", description="Total number of operations executed", unit="operations"
         )
 
+        # LLM call latency histogram (in seconds)
+        # Records duration of LLM API calls with provider, model, and scope dimensions
+        self.llm_duration = self.meter.create_histogram(
+            name="hindsight.llm.duration", description="Duration of LLM API calls in seconds", unit="s"
+        )
+
+        # LLM token usage counters with bucket labels
+        self.llm_tokens_input = self.meter.create_counter(
+            name="hindsight.llm.tokens.input", description="Number of input tokens for LLM calls", unit="tokens"
+        )
+
+        self.llm_tokens_output = self.meter.create_counter(
+            name="hindsight.llm.tokens.output", description="Number of output tokens from LLM calls", unit="tokens"
+        )
+
+        # LLM call counter (success/failure)
+        self.llm_calls_total = self.meter.create_counter(
+            name="hindsight.llm.calls.total", description="Total number of LLM API calls", unit="calls"
+        )
+
+        # HTTP request metrics
+        self.http_request_duration = self.meter.create_histogram(
+            name="hindsight.http.duration", description="Duration of HTTP requests in seconds", unit="s"
+        )
+
+        self.http_requests_total = self.meter.create_counter(
+            name="hindsight.http.requests.total", description="Total number of HTTP requests", unit="requests"
+        )
+
+        self.http_requests_in_progress = self.meter.create_up_down_counter(
+            name="hindsight.http.requests.in_progress",
+            description="Number of HTTP requests in progress",
+            unit="requests",
+        )
+
+        # Process metrics (observable gauges - collected on scrape)
+        self._setup_process_metrics()
+
+        # DB pool metrics holder (set via set_db_pool)
+        self._db_pool: "asyncpg.Pool | None" = None
+
     @contextmanager
-    def record_operation(self, operation: str, bank_id: str, budget: str | None = None, max_tokens: int | None = None):
+    def record_operation(
+        self,
+        operation: str,
+        bank_id: str,
+        source: str = "api",
+        budget: str | None = None,
+        max_tokens: int | None = None,
+    ):
         """
         Context manager to record operation duration and status.
 
         Usage:
-            with metrics.record_operation("recall", bank_id="user123", budget="mid", max_tokens=4096):
+            with metrics.record_operation("recall", bank_id="user123", source="api", budget="mid", max_tokens=4096):
                 # ... perform operation
                 pass
 
         Args:
-            operation: Operation name (retain, recall, reflect)
+            operation: Operation name (retain, recall, reflect, entity_observation)
             bank_id: Memory bank ID
+            source: Source of the operation (api, reflect, internal)
             budget: Optional budget level (low, mid, high)
             max_tokens: Optional max tokens for the operation
         """
@@ -159,6 +331,8 @@ class MetricsCollector(MetricsCollectorBase):
         attributes = {
             "operation": operation,
             "bank_id": bank_id,
+            "source": source,
+            "tenant": _get_tenant(),
         }
         if budget:
             attributes["budget"] = budget
@@ -181,40 +355,251 @@ class MetricsCollector(MetricsCollectorBase):
             # Record operation count
             self.operation_total.add(1, attributes)
 
-    def record_tokens(
+    def record_llm_call(
         self,
-        operation: str,
-        bank_id: str,
+        provider: str,
+        model: str,
+        scope: str,
+        duration: float,
         input_tokens: int = 0,
         output_tokens: int = 0,
-        budget: str | None = None,
-        max_tokens: int | None = None,
+        success: bool = True,
     ):
         """
-        Record token usage for an operation.
+        Record metrics for an LLM call.
 
         Args:
-            operation: Operation name (retain, recall, reflect)
-            bank_id: Memory bank ID
-            input_tokens: Number of input tokens
-            output_tokens: Number of output tokens
-            budget: Optional budget level
-            max_tokens: Optional max tokens for the operation
+            provider: LLM provider name (openai, anthropic, gemini, groq, ollama, lmstudio)
+            model: Model name
+            scope: Scope identifier (e.g., "memory", "reflect", "entity_observation")
+            duration: Call duration in seconds
+            input_tokens: Number of input/prompt tokens
+            output_tokens: Number of output/completion tokens
+            success: Whether the call was successful
         """
-        attributes = {
-            "operation": operation,
-            "bank_id": bank_id,
+        # Base attributes for all metrics
+        base_attributes = {
+            "provider": provider,
+            "model": model,
+            "scope": scope,
+            "success": str(success).lower(),
+            "tenant": _get_tenant(),
         }
-        if budget:
-            attributes["budget"] = budget
-        if max_tokens:
-            attributes["max_tokens"] = str(max_tokens)
 
+        # Record duration
+        self.llm_duration.record(duration, base_attributes)
+
+        # Record call count
+        self.llm_calls_total.add(1, base_attributes)
+
+        # Record tokens with bucket labels for cardinality control
         if input_tokens > 0:
-            self.tokens_input.add(input_tokens, attributes)
+            input_attributes = {
+                **base_attributes,
+                "token_bucket": get_token_bucket(input_tokens),
+            }
+            self.llm_tokens_input.add(input_tokens, input_attributes)
 
         if output_tokens > 0:
-            self.tokens_output.add(output_tokens, attributes)
+            output_attributes = {
+                **base_attributes,
+                "token_bucket": get_token_bucket(output_tokens),
+            }
+            self.llm_tokens_output.add(output_tokens, output_attributes)
+
+    @contextmanager
+    def record_http_request(self, method: str, endpoint: str, status_code_getter: Callable[[], int]):
+        """
+        Context manager to record HTTP request metrics.
+
+        Usage:
+            status_code = [200]  # Use list for mutability
+            with metrics.record_http_request("GET", "/api/banks", lambda: status_code[0]):
+                # ... handle request
+                status_code[0] = response.status_code
+
+        Args:
+            method: HTTP method (GET, POST, etc.)
+            endpoint: Request endpoint path
+            status_code_getter: Callable that returns the status code after request completes
+        """
+        start_time = time.time()
+        base_attributes = {"method": method, "endpoint": endpoint}
+
+        # Track in-progress
+        self.http_requests_in_progress.add(1, base_attributes)
+
+        try:
+            yield
+        finally:
+            duration = time.time() - start_time
+            status_code = status_code_getter()
+            status_class = f"{status_code // 100}xx"
+
+            # Get tenant from context (may be set during request processing)
+            tenant = _get_tenant()
+
+            attributes = {
+                **base_attributes,
+                "status_code": str(status_code),
+                "status_class": status_class,
+                "tenant": tenant,
+            }
+
+            # Record duration and count
+            self.http_request_duration.record(duration, attributes)
+            self.http_requests_total.add(1, attributes)
+
+            # Decrement in-progress
+            self.http_requests_in_progress.add(-1, base_attributes)
+
+    def _setup_process_metrics(self):
+        """Set up observable gauges for process metrics."""
+
+        def get_cpu_times(_options):
+            """Get process CPU times."""
+            try:
+                rusage = resource.getrusage(resource.RUSAGE_SELF)
+                yield metrics.Observation(rusage.ru_utime, {"type": "user"})
+                yield metrics.Observation(rusage.ru_stime, {"type": "system"})
+            except Exception:
+                pass
+
+        def get_memory_usage(_options):
+            """Get process memory usage in bytes."""
+            try:
+                rusage = resource.getrusage(resource.RUSAGE_SELF)
+                # ru_maxrss is in kilobytes on Linux, bytes on macOS
+                max_rss = rusage.ru_maxrss
+                if os.uname().sysname == "Linux":
+                    max_rss *= 1024  # Convert KB to bytes
+                yield metrics.Observation(max_rss, {"type": "rss_max"})
+            except Exception:
+                pass
+
+        def get_open_file_descriptors(_options):
+            """Get number of open file descriptors."""
+            try:
+                # Try to count open FDs by checking /proc on Linux
+                if os.path.exists("/proc/self/fd"):
+                    count = len(os.listdir("/proc/self/fd"))
+                    yield metrics.Observation(count)
+                else:
+                    # Fallback: use resource limits
+                    soft, hard = resource.getrlimit(resource.RLIMIT_NOFILE)
+                    yield metrics.Observation(soft, {"limit": "soft"})
+            except Exception:
+                pass
+
+        def get_thread_count(_options):
+            """Get number of active threads."""
+            try:
+                yield metrics.Observation(threading.active_count())
+            except Exception:
+                pass
+
+        # Create observable gauges
+        self.meter.create_observable_gauge(
+            name="hindsight.process.cpu.seconds",
+            callbacks=[get_cpu_times],
+            description="Process CPU time in seconds",
+            unit="s",
+        )
+
+        self.meter.create_observable_gauge(
+            name="hindsight.process.memory.bytes",
+            callbacks=[get_memory_usage],
+            description="Process memory usage in bytes",
+            unit="By",
+        )
+
+        self.meter.create_observable_gauge(
+            name="hindsight.process.open_fds",
+            callbacks=[get_open_file_descriptors],
+            description="Number of open file descriptors",
+            unit="{fds}",
+        )
+
+        self.meter.create_observable_gauge(
+            name="hindsight.process.threads",
+            callbacks=[get_thread_count],
+            description="Number of active threads",
+            unit="{threads}",
+        )
+
+    def set_db_pool(self, pool: "asyncpg.Pool"):
+        """
+        Set the database pool for metrics collection.
+
+        Args:
+            pool: asyncpg connection pool instance
+        """
+        self._db_pool = pool
+        self._setup_db_pool_metrics()
+
+    def _setup_db_pool_metrics(self):
+        """Set up observable gauges for database pool metrics."""
+
+        def get_pool_size(_options):
+            """Get current pool size."""
+            if self._db_pool is not None:
+                try:
+                    yield metrics.Observation(self._db_pool.get_size())
+                except Exception:
+                    pass
+
+        def get_pool_free_size(_options):
+            """Get number of free connections in pool."""
+            if self._db_pool is not None:
+                try:
+                    yield metrics.Observation(self._db_pool.get_idle_size())
+                except Exception:
+                    pass
+
+        def get_pool_min_size(_options):
+            """Get pool minimum size."""
+            if self._db_pool is not None:
+                try:
+                    yield metrics.Observation(self._db_pool.get_min_size())
+                except Exception:
+                    pass
+
+        def get_pool_max_size(_options):
+            """Get pool maximum size."""
+            if self._db_pool is not None:
+                try:
+                    yield metrics.Observation(self._db_pool.get_max_size())
+                except Exception:
+                    pass
+
+        # Create observable gauges for pool metrics
+        self.meter.create_observable_gauge(
+            name="hindsight.db.pool.size",
+            callbacks=[get_pool_size],
+            description="Current number of connections in the pool",
+            unit="{connections}",
+        )
+
+        self.meter.create_observable_gauge(
+            name="hindsight.db.pool.idle",
+            callbacks=[get_pool_free_size],
+            description="Number of idle connections in the pool",
+            unit="{connections}",
+        )
+
+        self.meter.create_observable_gauge(
+            name="hindsight.db.pool.min",
+            callbacks=[get_pool_min_size],
+            description="Minimum pool size",
+            unit="{connections}",
+        )
+
+        self.meter.create_observable_gauge(
+            name="hindsight.db.pool.max",
+            callbacks=[get_pool_max_size],
+            description="Maximum pool size",
+            unit="{connections}",
+        )
 
 
 # Global metrics collector instance (defaults to no-op)

hindsight-api/hindsight_api/migrations.py

@@ -6,18 +6,23 @@ on application startup. It is designed to be safe for concurrent
 execution using PostgreSQL advisory locks to coordinate between
 distributed workers.
 
+Supports multi-tenant schema isolation: migrations can target a specific
+PostgreSQL schema, allowing each tenant to have isolated tables.
+
 Important: All migrations must be backward-compatible to allow
 safe rolling deployments.
 
 No alembic.ini required - all configuration is done programmatically.
 """
 
+import hashlib
 import logging
 import os
 from pathlib import Path
 
 from alembic import command
 from alembic.config import Config
+from alembic.script.revision import ResolutionError
 from sqlalchemy import create_engine, text
 
 logger = logging.getLogger(__name__)
@@ -26,11 +31,29 @@ logger = logging.getLogger(__name__)
 MIGRATION_LOCK_ID = 123456789
 
 
-def _run_migrations_internal(database_url: str, script_location: str) -> None:
+def _get_schema_lock_id(schema: str) -> int:
+    """
+    Generate a unique advisory lock ID for a schema.
+
+    Uses hash of schema name to create a deterministic lock ID.
+    """
+    # Use hash to create a unique lock ID per schema
+    # Keep within PostgreSQL's bigint range
+    hash_bytes = hashlib.sha256(schema.encode()).digest()[:8]
+    return int.from_bytes(hash_bytes, byteorder="big") % (2**31)
+
+
+def _run_migrations_internal(database_url: str, script_location: str, schema: str | None = None) -> None:
     """
     Internal function to run migrations without locking.
+
+    Args:
+        database_url: SQLAlchemy database URL
+        script_location: Path to alembic scripts
+        schema: Target schema (None for default/public)
     """
-    logger.info("Running database migrations to head...")
+    schema_name = schema or "public"
+    logger.info(f"Running database migrations to head for schema '{schema_name}'...")
     logger.info(f"Database URL: {database_url}")
     logger.info(f"Script location: {script_location}")
 
@@ -50,13 +73,33 @@ def _run_migrations_internal(database_url: str, script_location: str) -> None:
     # Set path_separator to avoid deprecation warning
     alembic_cfg.set_main_option("path_separator", "os")
 
-    # Run migrations to head (latest version)
-    command.upgrade(alembic_cfg, "head")
+    # If targeting a specific schema, pass it to env.py via config
+    # env.py will handle setting search_path and version_table_schema
+    if schema:
+        alembic_cfg.set_main_option("target_schema", schema)
 
-    logger.info("Database migrations completed successfully")
+    # Run migrations
+    try:
+        command.upgrade(alembic_cfg, "head")
+    except ResolutionError as e:
+        # This happens during rolling deployments when a newer version of the code
+        # has already run migrations, and this older replica doesn't have the new
+        # migration files. The database is already at a newer revision than we know.
+        # This is safe to ignore - the newer code has already applied its migrations.
+        logger.warning(
+            f"Database is at a newer migration revision than this code version knows about. "
+            f"This is expected during rolling deployments. Skipping migrations. Error: {e}"
+        )
+        return
+
+    logger.info(f"Database migrations completed successfully for schema '{schema_name}'")
 
 
-def run_migrations(database_url: str, script_location: str | None = None) -> None:
+def run_migrations(
+    database_url: str,
+    script_location: str | None = None,
+    schema: str | None = None,
+) -> None:
     """
     Run database migrations to the latest version using programmatic Alembic configuration.
 
@@ -65,19 +108,28 @@ def run_migrations(database_url: str, script_location: str | None = None) -> Non
     - Other workers wait for the lock, then verify migrations are complete
     - If schema is already up-to-date, this is a fast no-op
 
+    Supports multi-tenant schema isolation: when a schema is specified, migrations
+    run in that schema instead of public. This allows tenant extensions to provision
+    new tenant schemas with their own isolated tables.
+
     Args:
         database_url: SQLAlchemy database URL (e.g., "postgresql://user:pass@host/db")
         script_location: Path to alembic migrations directory (e.g., "/path/to/alembic").
                         If None, defaults to hindsight-api/alembic directory.
+        schema: Target PostgreSQL schema name. If None, uses default (public).
+                When specified, creates the schema if needed and runs migrations there.
 
     Raises:
         RuntimeError: If migrations fail to complete
         FileNotFoundError: If script_location doesn't exist
 
     Example:
-        # Using default location (hindsight_api package)
+        # Using default location and public schema
         run_migrations("postgresql://user:pass@host/db")
 
+        # Run migrations for a specific tenant schema
+        run_migrations("postgresql://user:pass@host/db", schema="tenant_acme")
+
         # Using custom location (when importing from another project)
         run_migrations(
             "postgresql://user:pass@host/db",
@@ -99,21 +151,25 @@ def run_migrations(database_url: str, script_location: str | None = None) -> Non
                 f"Alembic script location not found at {script_location}. Database migrations cannot be run."
             )
 
+        # Use schema-specific lock ID for multi-tenant isolation
+        lock_id = _get_schema_lock_id(schema) if schema else MIGRATION_LOCK_ID
+        schema_name = schema or "public"
+
         # Use PostgreSQL advisory lock to coordinate between distributed workers
         engine = create_engine(database_url)
         with engine.connect() as conn:
             # pg_advisory_lock blocks until the lock is acquired
             # The lock is automatically released when the connection closes
-            logger.debug(f"Acquiring migration advisory lock (id={MIGRATION_LOCK_ID})...")
-            conn.execute(text(f"SELECT pg_advisory_lock({MIGRATION_LOCK_ID})"))
+            logger.debug(f"Acquiring migration advisory lock for schema '{schema_name}' (id={lock_id})...")
+            conn.execute(text(f"SELECT pg_advisory_lock({lock_id})"))
             logger.debug("Migration advisory lock acquired")
 
             try:
                 # Run migrations while holding the lock
-                _run_migrations_internal(database_url, script_location)
+                _run_migrations_internal(database_url, script_location, schema=schema)
             finally:
                 # Explicitly release the lock (also released on connection close)
-                conn.execute(text(f"SELECT pg_advisory_unlock({MIGRATION_LOCK_ID})"))
+                conn.execute(text(f"SELECT pg_advisory_unlock({lock_id})"))
                 logger.debug("Migration advisory lock released")
 
     except FileNotFoundError:
@@ -185,3 +241,131 @@ def check_migration_status(
     except Exception as e:
         logger.warning(f"Unable to check migration status: {e}")
         return None, None
+
+
+def ensure_embedding_dimension(
+    database_url: str,
+    required_dimension: int,
+    schema: str | None = None,
+) -> None:
+    """
+    Ensure the embedding column dimension matches the model's dimension.
+
+    This function checks the current vector column dimension in the database
+    and adjusts it if necessary:
+    - If dimensions match: no action needed
+    - If dimensions differ and table is empty: ALTER COLUMN to new dimension
+    - If dimensions differ and table has data: raise error with migration guidance
+
+    Args:
+        database_url: SQLAlchemy database URL
+        required_dimension: The embedding dimension required by the model
+        schema: Target PostgreSQL schema name (None for public)
+
+    Raises:
+        RuntimeError: If dimension mismatch with existing data
+    """
+    schema_name = schema or "public"
+
+    engine = create_engine(database_url)
+    with engine.connect() as conn:
+        # Check if memory_units table exists
+        table_exists = conn.execute(
+            text("""
+                SELECT EXISTS (
+                    SELECT 1 FROM information_schema.tables
+                    WHERE table_schema = :schema AND table_name = 'memory_units'
+                )
+            """),
+            {"schema": schema_name},
+        ).scalar()
+
+        if not table_exists:
+            logger.debug(f"memory_units table does not exist in schema '{schema_name}', skipping dimension check")
+            return
+
+        # Get current column dimension from pg_attribute
+        # pgvector stores dimension in atttypmod
+        current_dim = conn.execute(
+            text("""
+                SELECT atttypmod
+                FROM pg_attribute a
+                JOIN pg_class c ON a.attrelid = c.oid
+                JOIN pg_namespace n ON c.relnamespace = n.oid
+                WHERE n.nspname = :schema
+                  AND c.relname = 'memory_units'
+                  AND a.attname = 'embedding'
+            """),
+            {"schema": schema_name},
+        ).scalar()
+
+        if current_dim is None:
+            logger.warning("Could not determine current embedding dimension, skipping check")
+            return
+
+        # pgvector stores dimension directly in atttypmod (no offset like other types)
+        current_dimension = current_dim
+
+        if current_dimension == required_dimension:
+            logger.debug(f"Embedding dimension OK: {current_dimension}")
+            return
+
+        logger.info(
+            f"Embedding dimension mismatch: database has {current_dimension}, model requires {required_dimension}"
+        )
+
+        # Check if table has data
+        row_count = conn.execute(
+            text(f"SELECT COUNT(*) FROM {schema_name}.memory_units WHERE embedding IS NOT NULL")
+        ).scalar()
+
+        if row_count > 0:
+            raise RuntimeError(
+                f"Cannot change embedding dimension from {current_dimension} to {required_dimension}: "
+                f"memory_units table contains {row_count} rows with embeddings. "
+                f"To change dimensions, you must either:\n"
+                f"  1. Re-embed all data: DELETE FROM {schema_name}.memory_units; then restart\n"
+                f"  2. Use a model with {current_dimension}-dimensional embeddings"
+            )
+
+        # Table is empty, safe to alter column
+        logger.info(f"Altering embedding column dimension from {current_dimension} to {required_dimension}")
+
+        # Drop the HNSW index on embedding column if it exists
+        # Only drop indexes that use 'hnsw' and reference the 'embedding' column
+        conn.execute(
+            text(f"""
+                DO $$
+                DECLARE idx_name TEXT;
+                BEGIN
+                    FOR idx_name IN
+                        SELECT indexname FROM pg_indexes
+                        WHERE schemaname = '{schema_name}'
+                          AND tablename = 'memory_units'
+                          AND indexdef LIKE '%hnsw%'
+                          AND indexdef LIKE '%embedding%'
+                    LOOP
+                        EXECUTE 'DROP INDEX IF EXISTS {schema_name}.' || idx_name;
+                    END LOOP;
+                END $$;
+            """)
+        )
+
+        # Alter the column type
+        conn.execute(
+            text(f"ALTER TABLE {schema_name}.memory_units ALTER COLUMN embedding TYPE vector({required_dimension})")
+        )
+        conn.commit()
+
+        # Recreate the HNSW index
+        conn.execute(
+            text(f"""
+                CREATE INDEX IF NOT EXISTS idx_memory_units_embedding_hnsw
+                ON {schema_name}.memory_units
+                USING hnsw (embedding vector_cosine_ops)
+                WITH (m = 16, ef_construction = 64)
+            """)
+        )
+        conn.commit()
+
+        logger.info(f"Successfully changed embedding dimension to {required_dimension}")

hindsight-api/hindsight_api/models.py

@@ -2,9 +2,27 @@
 SQLAlchemy models for the memory system.
 """
 
+from dataclasses import dataclass
 from datetime import datetime
 from uuid import UUID as PyUUID
 
+
+@dataclass
+class RequestContext:
+    """
+    Context for request authentication and authorization.
+
+    This dataclass carries authentication data from HTTP requests to the
+    memory engine operations. It can be extended to include additional
+    context like headers, tokens, user info, etc.
+    """
+
+    api_key: str | None = None
+    api_key_id: str | None = None  # UUID of the API key used for authentication
+    tenant_id: str | None = None  # Tenant identifier (set by extension after auth)
+    internal: bool = False  # True for background/internal operations (not user-visible)
+
+
 from pgvector.sqlalchemy import Vector
 from sqlalchemy import (
     CheckConstraint,
@@ -23,6 +41,8 @@ from sqlalchemy.dialects.postgresql import JSONB, TIMESTAMP, UUID
 from sqlalchemy.ext.asyncio import AsyncAttrs
 from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column, relationship
 
+from .config import EMBEDDING_DIMENSION
+
 
 class Base(AsyncAttrs, DeclarativeBase):
     """Base class for all models."""
@@ -63,7 +83,7 @@ class MemoryUnit(Base):
     bank_id: Mapped[str] = mapped_column(Text, nullable=False)
     document_id: Mapped[str | None] = mapped_column(Text)
     text: Mapped[str] = mapped_column(Text, nullable=False)
-    embedding = mapped_column(Vector(384))  # pgvector type
+    embedding = mapped_column(Vector(EMBEDDING_DIMENSION))  # pgvector type
     context: Mapped[str | None] = mapped_column(Text)
     event_date: Mapped[datetime] = mapped_column(
         TIMESTAMP(timezone=True), nullable=False

hindsight-api/hindsight_api/pg0.py

@@ -40,7 +40,7 @@ class EmbeddedPostgres:
             # Only set port if explicitly specified
             if self.port is not None:
                 kwargs["port"] = self.port
-            self._pg0 = Pg0(**kwargs)
+            self._pg0 = Pg0(**kwargs)  # type: ignore[invalid-argument-type] - dict kwargs
         return self._pg0
 
     async def start(self, max_retries: int = 5, retry_delay: float = 4.0) -> str:
@@ -132,3 +132,56 @@ async def stop_embedded_postgres() -> None:
     global _default_instance
     if _default_instance:
         await _default_instance.stop()
+
+
+def parse_pg0_url(db_url: str) -> tuple[bool, str | None, int | None]:
+    """
+    Parse a database URL and check if it's a pg0:// embedded database URL.
+
+    Supports:
+    - "pg0" -> default instance "hindsight"
+    - "pg0://instance-name" -> named instance
+    - "pg0://instance-name:port" -> named instance with explicit port
+    - Any other URL (e.g., postgresql://) -> not a pg0 URL
+
+    Args:
+        db_url: The database URL to parse
+
+    Returns:
+        Tuple of (is_pg0, instance_name, port)
+        - is_pg0: True if this is a pg0 URL
+        - instance_name: The instance name (or None if not pg0)
+        - port: The explicit port (or None for auto-assign)
+    """
+    if db_url == "pg0":
+        return True, "hindsight", None
+
+    if db_url.startswith("pg0://"):
+        url_part = db_url[6:]  # Remove "pg0://"
+        if ":" in url_part:
+            instance_name, port_str = url_part.rsplit(":", 1)
+            return True, instance_name or "hindsight", int(port_str)
+        else:
+            return True, url_part or "hindsight", None
+
+    return False, None, None
+
+
+async def resolve_database_url(db_url: str) -> str:
+    """
+    Resolve a database URL, handling pg0:// embedded database URLs.
+
+    If the URL is a pg0:// URL, starts the embedded PostgreSQL and returns
+    the actual postgresql:// connection URL. Otherwise, returns the URL unchanged.
+
+    Args:
+        db_url: Database URL (pg0://, pg0, or postgresql://)
+
+    Returns:
+        The resolved postgresql:// connection URL
+    """
+    is_pg0, instance_name, port = parse_pg0_url(db_url)
+    if is_pg0:
+        pg0 = EmbeddedPostgres(name=instance_name, port=port)
+        return await pg0.ensure_running()
+    return db_url

hindsight-api/hindsight_api/server.py

@@ -7,6 +7,7 @@ This module provides the ASGI app for uvicorn import string usage:
 For CLI usage, use the hindsight-api command instead.
 """
 
+import logging
 import os
 import warnings
 
@@ -17,6 +18,12 @@ warnings.filterwarnings("ignore", message="websockets.server.WebSocketServerProt
 from hindsight_api import MemoryEngine
 from hindsight_api.api import create_app
 from hindsight_api.config import get_config
+from hindsight_api.extensions import (
+    DefaultExtensionContext,
+    OperationValidatorExtension,
+    TenantExtension,
+    load_extension,
+)
 
 # Disable tokenizers parallelism to avoid warnings
 os.environ["TOKENIZERS_PARALLELISM"] = "false"
@@ -25,12 +32,42 @@ os.environ["TOKENIZERS_PARALLELISM"] = "false"
 config = get_config()
 config.configure_logging()
 
+# Load operation validator extension if configured
+operation_validator = load_extension("OPERATION_VALIDATOR", OperationValidatorExtension)
+if operation_validator:
+    logging.info(f"Loaded operation validator: {operation_validator.__class__.__name__}")
+
+# Load tenant extension if configured
+tenant_extension = load_extension("TENANT", TenantExtension)
+if tenant_extension:
+    logging.info(f"Loaded tenant extension: {tenant_extension.__class__.__name__}")
+
 # Create app at module level (required for uvicorn import string)
 # MemoryEngine reads configuration from environment variables automatically
-_memory = MemoryEngine()
+# Note: run_migrations=True by default, but migrations are idempotent so safe with workers
+_memory = MemoryEngine(
+    operation_validator=operation_validator,
+    tenant_extension=tenant_extension,
+    run_migrations=config.run_migrations_on_startup,
+)
+
+# Set extension context on tenant extension (needed for schema provisioning)
+if tenant_extension:
+    extension_context = DefaultExtensionContext(
+        database_url=config.database_url,
+        memory_engine=_memory,
+    )
+    tenant_extension.set_context(extension_context)
+    logging.info("Extension context set on tenant extension")
 
 # Create unified app with both HTTP and optionally MCP
-app = create_app(memory=_memory, http_api_enabled=True, mcp_api_enabled=config.mcp_enabled, mcp_mount_path="/mcp")
+app = create_app(
+    memory=_memory,
+    http_api_enabled=True,
+    mcp_api_enabled=config.mcp_enabled,
+    mcp_mount_path="/mcp",
+    initialize_memory=True,
+)
 
 
 if __name__ == "__main__":

hindsight-api/pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "hindsight-api"
-version = "0.1.11"
+version = "0.3.0"
 description = "Hindsight: Agent Memory That Works Like Human Memory"
 readme = "README.md"
 requires-python = ">=3.11"
@@ -14,7 +14,6 @@ dependencies = [
     "openai>=1.0.0",
     "pydantic>=2.0.0",
     "rich>=13.0.0",
-    "sentence-transformers>=3.0.0,<3.3.0",
     "langchain-text-splitters>=0.3.0",
     "fastapi[standard]>=0.120.3",
     "uvicorn>=0.38.0",
@@ -24,8 +23,6 @@ dependencies = [
     "pgvector>=0.4.1",
     "greenlet>=3.2.4",
     "psycopg2-binary>=2.9.11",
-    "transformers>=4.30.0,<4.46.0",
-    "torch>=2.0.0",
     "tiktoken>=0.12.0",
     "httpx>=0.27.0",
     "fastmcp>=2.3.0",
@@ -37,6 +34,15 @@ dependencies = [
     "opentelemetry-exporter-prometheus>=0.41b0",
     "dateparser>=1.2.2",
     "google-genai>=1.0.0",
+    "anthropic>=0.40.0",
+    "typer>=0.9.0",
+    "cohere>=5.0.0",
+    "flashrank>=0.2.0",
+    # Local ML models for embeddings/reranking - can be excluded in Docker with INCLUDE_LOCAL_MODELS=false
+    "sentence-transformers>=3.0.0,<3.3.0",
+    "transformers>=4.30.0,<4.46.0",
+    "torch>=2.0.0",
+    "uvloop>=0.22.1",
 ]
 
 [project.optional-dependencies]
@@ -51,6 +57,7 @@ test = [
 [project.scripts]
 hindsight-api = "hindsight_api.main:main"
 hindsight-local-mcp = "hindsight_api.mcp_local:main"
+hindsight-admin = "hindsight_api.admin.cli:main"
 
 [tool.hatch.build.targets.wheel]
 packages = ["hindsight_api"]
@@ -74,7 +81,7 @@ log_cli = true
 log_cli_level = "INFO"
 log_cli_format = "%(asctime)s - %(levelname)s - %(name)s - %(message)s"
 log_cli_date_format = "%Y-%m-%d %H:%M:%S"
-addopts = "--timeout 120 -n 8 --durations=10 -v"
+addopts = "--timeout 120 -n 8 --dist loadgroup --durations=10 -v"
 asyncio_mode = "auto"
 asyncio_default_fixture_loop_scope = "function"
 log_auto_indent = true
@@ -92,6 +99,7 @@ dev = [
     "python-dotenv>=1.2.1",
     "filelock>=3.0.0",
     "ruff>=0.8.0",
+    "ty>=0.0.1",
 ]
 
 [tool.ruff]
@@ -118,6 +126,34 @@ ignore = [
     "F821",   # undefined name (forward references in type hints)
 ]
 
+[tool.ruff.lint.isort]
+known-third-party = ["alembic"]
+
 [tool.ruff.format]
 quote-style = "double"
 indent-style = "space"
+
+[tool.ty]
+# Type checking configuration
+# ty is an extremely fast Python type checker from Astral (same team as ruff/uv)
+
+[tool.ty.environment]
+python-version = "3.11"
+
+[tool.ty.src]
+exclude = [
+    "tests/",
+    "hindsight_api/alembic/",
+]
+
+[tool.ty.rules]
+# Disable noisy rules while keeping important ones
+invalid-argument-type = "ignore"    # False positives with **kwargs patterns
+invalid-return-type = "ignore"      # Often intentional in async code
+invalid-parameter-default = "ignore" # Optional params with None default
+possibly-missing-attribute = "ignore" # Common with Optional types
+invalid-raise = "ignore"            # False positives with exception tracking
+call-non-callable = "ignore"        # False positives with Optional types
+invalid-key = "ignore"              # Pydantic ConfigDict not understood
+invalid-method-override = "ignore"  # Intentional signature differences
+unresolved-reference = "ignore"     # Forward references not always resolved

hindsight-api/tests/conftest.py

@@ -8,7 +8,7 @@ import os
 import filelock
 from pathlib import Path
 from dotenv import load_dotenv
-from hindsight_api import MemoryEngine, LLMConfig, LocalSTEmbeddings
+from hindsight_api import MemoryEngine, LLMConfig, LocalSTEmbeddings, RequestContext
 
 from hindsight_api.engine.cross_encoder import LocalSTCrossEncoder
 from hindsight_api.engine.query_analyzer import DateparserQueryAnalyzer
@@ -99,6 +99,12 @@ def pg0_db_url(db_url, tmp_path_factory, worker_id):
     return url
 
 
+@pytest.fixture(scope="function")
+def request_context():
+    """Provide a default RequestContext for tests."""
+    return RequestContext()
+
+
 @pytest.fixture(scope="session")
 def llm_config():
     """

hindsight-api/tests/test_admin_backup_restore.py

@@ -0,0 +1,292 @@
+"""
+Tests for admin backup and restore functionality.
+
+These tests use an isolated schema to avoid interfering with other tests.
+The backup/restore operations truncate tables, which would cause deadlocks
+and race conditions if run against the shared public schema.
+"""
+
+import tempfile
+import uuid
+import zipfile
+from pathlib import Path
+
+import asyncpg
+import pytest
+import pytest_asyncio
+
+from hindsight_api.admin.cli import _backup, _restore, BACKUP_TABLES
+from hindsight_api.migrations import run_migrations
+
+
+# Run these tests sequentially since they do full DB backup/restore
+pytestmark = pytest.mark.xdist_group(name="backup_restore")
+
+
+@pytest_asyncio.fixture(scope="function")
+async def backup_test_schema(pg0_db_url, embeddings):
+    """Create an isolated schema for backup/restore tests.
+
+    Uses a unique schema name per test invocation to avoid conflicts with
+    parallel test runs or leftover state from interrupted runs.
+
+    Returns a tuple of (db_url, schema_name, fq_helper, embeddings).
+    """
+    # Initialize embeddings if not already done
+    await embeddings.initialize()
+
+    # Use unique schema name to avoid conflicts
+    schema_name = f"backup_test_{uuid.uuid4().hex[:8]}"
+
+    def _fq(table: str) -> str:
+        """Get fully-qualified table name in test schema."""
+        return f"{schema_name}.{table}"
+
+    conn = await asyncpg.connect(pg0_db_url)
+    try:
+        await conn.execute(f"CREATE SCHEMA {schema_name}")
+    finally:
+        await conn.close()
+
+    # Run migrations on the isolated schema
+    run_migrations(pg0_db_url, schema=schema_name)
+
+    yield pg0_db_url, schema_name, _fq, embeddings
+
+    # Cleanup after test
+    conn = await asyncpg.connect(pg0_db_url)
+    try:
+        await conn.execute(f"DROP SCHEMA IF EXISTS {schema_name} CASCADE")
+    finally:
+        await conn.close()
+
+
+@pytest.mark.asyncio
+async def test_backup_restore_roundtrip(backup_test_schema):
+    """Test that backup and restore preserves all data correctly."""
+    db_url, schema_name, _fq, embeddings = backup_test_schema
+    bank_id = f"test-backup-{uuid.uuid4().hex[:8]}"
+    conn = await asyncpg.connect(db_url)
+
+    try:
+        # Create a bank
+        await conn.execute(
+            f"INSERT INTO {_fq('banks')} (bank_id) VALUES ($1) ON CONFLICT DO NOTHING",
+            bank_id,
+        )
+
+        # Create some test memory units with embeddings
+        # Convert embedding list to pgvector format string
+        embedding_list = embeddings.encode(["Test content about Alice"])[0]
+        embedding_str = "[" + ",".join(str(x) for x in embedding_list) + "]"
+        for text in [
+            "Alice is a software engineer who loves Python.",
+            "Bob works with Alice on the backend team.",
+            "The team uses PostgreSQL for their database.",
+        ]:
+            await conn.execute(
+                f"""INSERT INTO {_fq('memory_units')}
+                    (bank_id, text, fact_type, embedding, event_date)
+                    VALUES ($1, $2, 'world', $3::vector, NOW())""",
+                bank_id,
+                text,
+                embedding_str,
+            )
+
+        # Get counts before backup
+        counts_before = {}
+        for table in BACKUP_TABLES:
+            counts_before[table] = await conn.fetchval(f"SELECT COUNT(*) FROM {_fq(table)}")
+
+        # Verify we have data
+        assert counts_before["banks"] > 0
+        assert counts_before["memory_units"] > 0
+
+    finally:
+        await conn.close()
+
+    # Backup to a temp file
+    with tempfile.NamedTemporaryFile(suffix=".zip", delete=False) as f:
+        backup_path = Path(f.name)
+
+    try:
+        manifest = await _backup(db_url, backup_path, schema=schema_name)
+
+        # Verify backup file exists and is valid
+        assert backup_path.exists()
+        assert backup_path.stat().st_size > 0
+
+        # Verify manifest
+        assert manifest["version"] == "1"
+        assert "created_at" in manifest
+        for table in BACKUP_TABLES:
+            assert table in manifest["tables"]
+            assert manifest["tables"][table]["rows"] == counts_before[table]
+
+        # Verify zip contents
+        with zipfile.ZipFile(backup_path, "r") as zf:
+            assert "manifest.json" in zf.namelist()
+            for table in BACKUP_TABLES:
+                assert f"{table}.bin" in zf.namelist()
+
+        # Clear all data
+        conn = await asyncpg.connect(db_url)
+        try:
+            for table in reversed(BACKUP_TABLES):
+                await conn.execute(f"TRUNCATE TABLE {_fq(table)} CASCADE")
+
+            # Verify data is gone
+            for table in BACKUP_TABLES:
+                count = await conn.fetchval(f"SELECT COUNT(*) FROM {_fq(table)}")
+                assert count == 0, f"Table {table} should be empty after truncate"
+        finally:
+            await conn.close()
+
+        # Restore from backup
+        await _restore(db_url, backup_path, schema=schema_name)
+
+        # Verify counts match original
+        conn = await asyncpg.connect(db_url)
+        try:
+            for table in BACKUP_TABLES:
+                count = await conn.fetchval(f"SELECT COUNT(*) FROM {_fq(table)}")
+                assert count == counts_before[table], f"Table {table} count mismatch after restore"
+
+            # Verify data content is preserved
+            texts = await conn.fetch(
+                f"SELECT text FROM {_fq('memory_units')} WHERE bank_id = $1",
+                bank_id,
+            )
+            text_content = " ".join(r["text"] for r in texts)
+            assert "Alice" in text_content or "software" in text_content
+        finally:
+            await conn.close()
+
+    finally:
+        # Cleanup
+        if backup_path.exists():
+            backup_path.unlink()
+
+
+@pytest.mark.asyncio
+async def test_backup_restore_preserves_all_column_types(backup_test_schema):
+    """Test that all column types are preserved: vectors, UUIDs, timestamps, JSONB."""
+    db_url, schema_name, _fq, embeddings = backup_test_schema
+    bank_id = f"test-types-{uuid.uuid4().hex[:8]}"
+    conn = await asyncpg.connect(db_url)
+
+    try:
+        # Create a bank
+        await conn.execute(
+            f"INSERT INTO {_fq('banks')} (bank_id) VALUES ($1) ON CONFLICT DO NOTHING",
+            bank_id,
+        )
+
+        # Create a memory unit with all column types
+        # Convert embedding list to pgvector format string
+        embedding_list = embeddings.encode(["John Smith engineer"])[0]
+        embedding_str = "[" + ",".join(str(x) for x in embedding_list) + "]"
+        await conn.execute(
+            f"""INSERT INTO {_fq('memory_units')}
+                (bank_id, text, fact_type, embedding, event_date, metadata)
+                VALUES ($1, $2, 'world', $3::vector, NOW(), $4)""",
+            bank_id,
+            "John Smith is a senior engineer at Acme Corp since 2020.",
+            embedding_str,
+            '{"key": "value"}',
+        )
+
+        # Create an entity
+        await conn.execute(
+            f"""INSERT INTO {_fq('entities')}
+                (bank_id, canonical_name, metadata)
+                VALUES ($1, $2, $3)""",
+            bank_id,
+            "John Smith",
+            '{"role": "engineer"}',
+        )
+
+        # Get original data
+        original_unit = await conn.fetchrow(
+            f"""SELECT id, embedding, event_date, created_at, metadata, text
+               FROM {_fq('memory_units')} WHERE bank_id = $1 LIMIT 1""",
+            bank_id,
+        )
+        original_entity = await conn.fetchrow(
+            f"""SELECT id, first_seen, last_seen, metadata, canonical_name
+               FROM {_fq('entities')} WHERE bank_id = $1 LIMIT 1""",
+            bank_id,
+        )
+        original_bank = await conn.fetchrow(
+            f"SELECT bank_id, created_at, updated_at FROM {_fq('banks')} WHERE bank_id = $1",
+            bank_id,
+        )
+    finally:
+        await conn.close()
+
+    assert original_unit is not None, "Should have created memory units"
+    assert original_unit["embedding"] is not None, "Should have embedding"
+    assert original_unit["id"] is not None, "Should have UUID"
+    assert original_entity is not None, "Should have created entities"
+
+    with tempfile.NamedTemporaryFile(suffix=".zip", delete=False) as f:
+        backup_path = Path(f.name)
+
+    try:
+        await _backup(db_url, backup_path, schema=schema_name)
+
+        # Clear all data
+        conn = await asyncpg.connect(db_url)
+        try:
+            for table in reversed(BACKUP_TABLES):
+                await conn.execute(f"TRUNCATE TABLE {_fq(table)} CASCADE")
+        finally:
+            await conn.close()
+
+        await _restore(db_url, backup_path, schema=schema_name)
+
+        # Verify all column types are preserved exactly
+        conn = await asyncpg.connect(db_url)
+        try:
+            restored_unit = await conn.fetchrow(
+                f"""SELECT id, embedding, event_date, created_at, metadata, text
+                   FROM {_fq('memory_units')} WHERE bank_id = $1 LIMIT 1""",
+                bank_id,
+            )
+            restored_entity = await conn.fetchrow(
+                f"""SELECT id, first_seen, last_seen, metadata, canonical_name
+                   FROM {_fq('entities')} WHERE bank_id = $1 LIMIT 1""",
+                bank_id,
+            )
+            restored_bank = await conn.fetchrow(
+                f"SELECT bank_id, created_at, updated_at FROM {_fq('banks')} WHERE bank_id = $1",
+                bank_id,
+            )
+        finally:
+            await conn.close()
+
+        # Verify memory_units
+        assert restored_unit is not None, "Should have restored memory unit"
+        assert restored_unit["id"] == original_unit["id"], "UUID should match exactly"
+        assert restored_unit["text"] == original_unit["text"], "Text should match"
+        assert list(restored_unit["embedding"]) == list(original_unit["embedding"]), "Vector embedding should match exactly"
+        assert restored_unit["event_date"] == original_unit["event_date"], "Timestamp should match exactly"
+        assert restored_unit["created_at"] == original_unit["created_at"], "Created timestamp should match"
+        assert restored_unit["metadata"] == original_unit["metadata"], "JSONB metadata should match"
+
+        # Verify entities
+        assert restored_entity is not None, "Should have restored entity"
+        assert restored_entity["id"] == original_entity["id"], "Entity UUID should match"
+        assert restored_entity["canonical_name"] == original_entity["canonical_name"], "Entity name should match"
+        assert restored_entity["first_seen"] == original_entity["first_seen"], "Entity first_seen should match"
+        assert restored_entity["last_seen"] == original_entity["last_seen"], "Entity last_seen should match"
+        assert restored_entity["metadata"] == original_entity["metadata"], "Entity metadata should match"
+
+        # Verify banks
+        assert restored_bank is not None, "Should have restored bank"
+        assert restored_bank["bank_id"] == original_bank["bank_id"], "Bank ID should match"
+        assert restored_bank["created_at"] == original_bank["created_at"], "Bank created_at should match"
+
+    finally:
+        if backup_path.exists():
+            backup_path.unlink()