test: strengthen callback-manager filtering tests and document name fallback

- assert the inferred schema explicitly excludes run_manager/callbacks
- add a test case covering the async CallbackManagerForToolRun variant so
  both sync and async callback-manager types are exercised separately
- document why the run_manager/callbacks name fallback exists: this module
  uses from __future__ import annotations, so annotations arrive as strings
  and get_type_hints can fail to resolve them, leaving string annotations
  that the issubclass check cannot match

Signed-off-by: godququ5-code <godququ5@gmail.com>

Author: godququ5-code

python/packages/autogen-ext/src/autogen_ext/tools/langchain/_langchain_adapter.py

@@ -219,6 +219,13 @@ def __init__(self, langchain_tool: LangChainTool):
                 #   * ``callbacks`` (a ``Callbacks`` sequence of handlers) —
                 #     ``_is_callback_manager_annotation`` does not match it, so
                 #     it must be filtered by name.
+                # ``get_type_hints`` resolves annotations to real types when it
+                # can, but this module uses ``from __future__ import annotations``,
+                # so annotations arrive as strings and ``get_type_hints`` can fail
+                # (e.g. for a locally-defined tool), leaving a string annotation
+                # that ``_is_callback_manager_annotation``'s ``issubclass`` check
+                # cannot match. The ``run_manager``/``callbacks`` name check is a
+                # deliberate fallback for exactly that case.
                 annotation = type_hints.get(k, v.annotation)
                 if _is_callback_manager_annotation(annotation) or k in ("run_manager", "callbacks"):
                     continue

python/packages/autogen-ext/tests/tools/test_langchain_tools.py

@@ -133,6 +133,7 @@ async def test_langchain_tool_adapter_skips_run_manager() -> None:
     assert "parameters" in schema
     assert "properties" in schema["parameters"]
     props = schema["parameters"]["properties"]
+    assert "run_manager" not in props
     assert set(props.keys()) == {"a", "b"}
     assert "required" in schema["parameters"]
     assert set(schema["parameters"]["required"]) == {"a", "b"}
@@ -167,6 +168,46 @@ async def test_langchain_tool_adapter_skips_callbacks() -> None:
     assert "parameters" in schema
     assert "properties" in schema["parameters"]
     props = schema["parameters"]["properties"]
+    assert "callbacks" not in props
+    assert set(props.keys()) == {"a", "b"}
+    assert "required" in schema["parameters"]
+    assert set(schema["parameters"]["required"]) == {"a", "b"}
+
+    result = await adapter.run_json({"a": 2, "b": 3}, CancellationToken())
+    assert result == 5
+
+
+class NoSchemaAsyncManagerTool(LangChainTool):
+    name: str = "NoSchemaAsyncManager"
+    description: str = "a tool whose sync _run is annotated with the async callback manager type"
+
+    def _run(
+        self, a: int, b: int, run_manager: Optional[AsyncCallbackManagerForToolRun] = None
+    ) -> int:
+        return a + b
+
+    async def _arun(
+        self, a: int, b: int, run_manager: Optional[AsyncCallbackManagerForToolRun] = None
+    ) -> int:
+        return a + b
+
+
+@pytest.mark.asyncio
+async def test_langchain_tool_adapter_skips_async_run_manager() -> None:
+    # The detection must cover the *async* callback-manager type
+    # (``AsyncCallbackManagerForToolRun``), not only the sync
+    # ``CallbackManagerForToolRun``. ``_is_callback_manager_annotation`` unwraps
+    # ``Optional[...]`` and matches both via ``issubclass``, so a tool that
+    # annotates its signature with the async variant is still filtered out.
+    tool = NoSchemaAsyncManagerTool()
+    adapter = LangChainToolAdapter(tool)  # type: ignore
+
+    schema = adapter.schema
+    assert schema["name"] == "NoSchemaAsyncManager"
+    assert "parameters" in schema
+    assert "properties" in schema["parameters"]
+    props = schema["parameters"]["properties"]
+    assert "run_manager" not in props
     assert set(props.keys()) == {"a", "b"}
     assert "required" in schema["parameters"]
     assert set(schema["parameters"]["required"]) == {"a", "b"}