fix(langchain-sdk): Inherit from BaseTool and implement placeholder _run method.

This is some ground-work before we add sync tool calls support to ToolboxTool.

Author: anubhav756

src/toolbox_langchain_sdk/tools.py

@@ -17,7 +17,7 @@
 from warnings import warn
 
 from aiohttp import ClientSession
-from langchain_core.tools import StructuredTool
+from langchain_core.tools import BaseTool
 from typing_extensions import Self
 
 from .utils import (
@@ -30,7 +30,7 @@
 )
 
 
-class ToolboxTool(StructuredTool):
+class ToolboxTool(BaseTool):
     """
     A subclass of LangChain's StructuredTool that supports features specific to
     Toolbox, like bound parameters and authenticated tools.
@@ -120,8 +120,6 @@ def __init__(
         # Due to how pydantic works, we must initialize the underlying
         # StructuredTool class before assigning values to member variables.
         super().__init__(
-            coroutine=self.__tool_func,
-            func=None,
             name=name,
             description=schema.description,
             args_schema=_schema_to_model(model_name=name, schema=schema.parameters),
@@ -139,7 +137,7 @@ def __init__(
         # tool invocation.
         self.__validate_auth(strict=False)
 
-    async def __tool_func(self, **kwargs: Any) -> dict:
+    async def _arun(self, **kwargs: Any) -> dict[str, Any]:
         """
         The coroutine that invokes the tool with the given arguments.
 
@@ -171,6 +169,9 @@ async def __tool_func(self, **kwargs: Any) -> dict:
             self._url, self._session, self._name, kwargs, self._auth_tokens
         )
 
+    def _run(self, **kwargs: Any) -> dict[str, Any]:
+        raise NotImplementedError("Sync tool calls not supported yet.")
+
     def __validate_auth(self, strict: bool = True) -> None:
         """
         Checks if a tool meets the authentication requirements.

tests/test_tools.py

@@ -268,6 +268,14 @@ async def test_toolbox_tool_call(toolbox_tool):
         assert result == {"result": "test-result"}
 
 
+@pytest.mark.asyncio
+async def test_toolbox_sync_tool_call_(toolbox_tool):
+    async for tool in toolbox_tool:
+        with pytest.raises(NotImplementedError) as e:
+            result = tool.invoke({"param1": "test-value", "param2": 123})
+        assert "Sync tool calls not supported yet." in str(e.value)
+
+
 @pytest.mark.asyncio
 async def test_toolbox_tool_call_with_bound_params(toolbox_tool):
     async for tool in toolbox_tool: