fix(llamaindex): give HindsightMemory.from_defaults a real cloud-default ctor

Audit finding (2026-06-02): HindsightMemory's create paths are asymmetric
with what create_hindsight_tools offers. The tools factory uses
resolve_client() so callers get the standard cloud-default + env-var
fallback for free; the memory adapter required either an explicit client
(from_client) or an explicit URL (from_url) and its from_defaults() raised
NotImplementedError. Callers wanting the same "no-config → Cloud" path
had to wire it themselves.

Fix: from_defaults(bank_id, ...) now calls resolve_client() exactly the
way the tools factory does. Falls back to DEFAULT_HINDSIGHT_API_URL when
no URL is supplied; reads HINDSIGHT_API_KEY from the environment if no
api_key is supplied; explicit `client=` still wins.

Tests pinning the new behaviour:
- from_defaults with nothing supplied → Hindsight constructed with
  DEFAULT_HINDSIGHT_API_URL.
- from_defaults with api_key → constructed with the configured key.
- from_defaults with explicit client → no new Hindsight constructed.

Replaces the previous test_from_defaults_raises (which pinned the
NotImplementedError that we're removing).

Verification:
- Deterministic bucket: 86 pass / 4 deselected (84 prior + 2 new
  cloud-default tests; one prior raises-test rewritten).

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

hindsight-integrations/llamaindex/hindsight_llamaindex/memory.py

@@ -17,6 +17,8 @@ from llama_index.core.bridge.pydantic import Field, PrivateAttr
 from llama_index.core.llms import ChatMessage, MessageRole
 from llama_index.core.memory.types import BaseMemory
 
+from ._client import resolve_client
+
 logger = logging.getLogger(__name__)
 
 DEFAULT_SYSTEM_PROMPT = (
@@ -99,9 +101,59 @@ class HindsightMemory(BaseMemory):
         return "HindsightMemory"
 
     @classmethod
-    def from_defaults(cls, **kwargs: Any) -> "HindsightMemory":
-        """Create from defaults. Prefer ``from_client()`` instead."""
-        raise NotImplementedError("Use HindsightMemory.from_client() or HindsightMemory.from_url() instead.")
+    def from_defaults(
+        cls,
+        bank_id: str,
+        *,
+        client: Optional[Hindsight] = None,
+        hindsight_api_url: Optional[str] = None,
+        api_key: Optional[str] = None,
+        mission: Optional[str] = None,
+        context: str = "llamaindex",
+        budget: str = "mid",
+        max_tokens: int = 4096,
+        tags: Optional[list[str]] = None,
+        recall_tags: Optional[list[str]] = None,
+        recall_tags_match: str = "any",
+        system_prompt: str = DEFAULT_SYSTEM_PROMPT,
+        chat_history_limit: int = 100,
+        **kwargs: Any,
+    ) -> "HindsightMemory":
+        """Create a HindsightMemory using the shared client-resolution path.
+
+        Mirrors what ``create_hindsight_tools`` does for the tools factory:
+        when neither ``client`` nor ``hindsight_api_url`` is supplied, falls
+        back to ``DEFAULT_HINDSIGHT_API_URL`` (Hindsight Cloud) and reads
+        ``HINDSIGHT_API_KEY`` from the environment. Equivalent to
+        ``from_client(resolve_client(...), bank_id, ...)`` but spells out the
+        common cloud-default and env-var paths so callers don't have to wire
+        them themselves.
+
+        Args:
+            bank_id: Memory bank ID (required).
+            client: Pre-configured Hindsight client. Wins over URL/key.
+            hindsight_api_url: API URL. Defaults to the configured value or
+                ``DEFAULT_HINDSIGHT_API_URL``.
+            api_key: API key. Defaults to the configured value or
+                ``HINDSIGHT_API_KEY`` env var.
+            mission, context, budget, max_tokens, tags, recall_tags,
+                recall_tags_match, system_prompt, chat_history_limit:
+                Passed to ``from_client``.
+        """
+        resolved = resolve_client(client, hindsight_api_url, api_key)
+        return cls.from_client(
+            client=resolved,
+            bank_id=bank_id,
+            mission=mission,
+            context=context,
+            budget=budget,
+            max_tokens=max_tokens,
+            tags=tags,
+            recall_tags=recall_tags,
+            recall_tags_match=recall_tags_match,
+            system_prompt=system_prompt,
+            chat_history_limit=chat_history_limit,
+        )
 
     @classmethod
     def from_client(

hindsight-integrations/llamaindex/tests/test_memory.py

@@ -68,9 +68,42 @@ class TestHindsightMemoryCreation:
                 base_url="http://localhost:8888", timeout=30.0
             )
 
-    def test_from_defaults_raises(self):
-        with pytest.raises(NotImplementedError):
-            HindsightMemory.from_defaults()
+    def test_from_defaults_uses_cloud_default_when_nothing_supplied(self):
+        """Parity with create_hindsight_tools: no URL/key → DEFAULT_HINDSIGHT_API_URL.
+
+        Pins the cloud-default constructor that the 2026-06-02 audit asked for
+        — HindsightMemory used to require an explicit client or explicit URL,
+        leaving callers to wire the cloud-default themselves while the tools
+        factory did it for them.
+        """
+        from hindsight_llamaindex.config import DEFAULT_HINDSIGHT_API_URL
+        with patch("hindsight_llamaindex._client.Hindsight") as mock_cls:
+            mock_cls.return_value = _mock_client()
+            memory = HindsightMemory.from_defaults(bank_id="test-bank")
+            assert memory.bank_id == "test-bank"
+            kwargs = mock_cls.call_args.kwargs
+            assert kwargs.get("base_url") == DEFAULT_HINDSIGHT_API_URL
+
+    def test_from_defaults_threads_api_key_into_constructed_client(self):
+        """When api_key is provided, resolve_client must include it."""
+        with patch("hindsight_llamaindex._client.Hindsight") as mock_cls:
+            mock_cls.return_value = _mock_client()
+            HindsightMemory.from_defaults(
+                bank_id="test-bank",
+                api_key="hsk_test_key_42",
+            )
+            kwargs = mock_cls.call_args.kwargs
+            assert kwargs.get("api_key") == "hsk_test_key_42"
+
+    def test_from_defaults_explicit_client_wins(self):
+        """When client is given, no new Hindsight is constructed."""
+        client = _mock_client()
+        with patch("hindsight_llamaindex._client.Hindsight") as mock_cls:
+            memory = HindsightMemory.from_defaults(
+                bank_id="test-bank", client=client
+            )
+            assert memory.bank_id == "test-bank"
+            mock_cls.assert_not_called()
 
     def test_class_name(self):
         assert HindsightMemory.class_name() == "HindsightMemory"