From 65edd20c33509693875aee299af294280475d2b4 Mon Sep 17 00:00:00 2001
From: mateo-berri <277851410+mateo-berri@users.noreply.github.com>
Date: Sat, 7 Nov 2026 05:41:11 -0800
Subject: [PATCH] refactor(mcp): type the semantic filter's default tool loader

Annotate the chosen loader as _OpenAIToolLoader and narrow its return to
FunctionToolParam, so a default that returns raw MCP tools fails the type
check. Drop the unused patch import.
---
 litellm/proxy/hooks/mcp_semantic_filter/hook.py          | 6 ++++--
 tests/unit/proxy/mcp_server/test_semantic_tool_filter.py | 2 +-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/litellm/proxy/hooks/mcp_semantic_filter/hook.py b/litellm/proxy/hooks/mcp_semantic_filter/hook.py
index 163e0243379..b7b65d6f0db 100644
--- a/litellm/proxy/hooks/mcp_semantic_filter/hook.py
+++ b/litellm/proxy/hooks/mcp_semantic_filter/hook.py
@@ -24,6 +24,8 @@ from litellm.proxy.mcp_server.semantic_tool_filter import (
 )
 
 if TYPE_CHECKING:
+    from openai.types.responses.function_tool_param import FunctionToolParam
+
     from litellm.caching.caching import DualCache
     from litellm.proxy._types import UserAPIKeyAuth
     from litellm.proxy.mcp_server.semantic_tool_filter import (
@@ -57,7 +59,7 @@ class _OpenAIToolLoader(Protocol):
         *,
         user_api_key_auth: "UserAPIKeyAuth | None",
         mcp_tools_with_litellm_proxy: Sequence[Mapping[str, object]],
-    ) -> Awaitable[tuple[Sequence[object], Mapping[str, str]]]: ...
+    ) -> Awaitable[tuple[Sequence["FunctionToolParam"], Mapping[str, str]]]: ...
 
 
 class _PydanticTool(Protocol):
@@ -155,7 +157,7 @@ class SemanticToolFilterHook(CustomLogger):
         if not mcp_tools:
             return []
 
-        load_openai_tools: Final = (
+        load_openai_tools: Final[_OpenAIToolLoader] = (
             LiteLLM_Proxy_MCP_Handler.process_mcp_tools_to_openai_format
             if self._load_openai_tools is None
             else self._load_openai_tools
diff --git a/tests/unit/proxy/mcp_server/test_semantic_tool_filter.py b/tests/unit/proxy/mcp_server/test_semantic_tool_filter.py
index 0b5cd82efd8..afbc439cb99 100644
--- a/tests/unit/proxy/mcp_server/test_semantic_tool_filter.py
+++ b/tests/unit/proxy/mcp_server/test_semantic_tool_filter.py
@@ -7,7 +7,7 @@ an ordered set of top K tools based on semantic similarity.
 
 import asyncio
 import sys
-from unittest.mock import AsyncMock, Mock, patch
+from unittest.mock import AsyncMock, Mock
 
 import pytest