fix(guardrails): keep OpenAI tool_search out of the Responses guardrail tool scan

The scan translated tool_search into Anthropic's regex search tool on every
route, so a guardrail returning only function tools removed tool_search from
native OpenAI requests and OpenAI answered 400 for the deferred tools

litellm/llms/openai/responses/guardrail_translation/handler.py

@@ -64,6 +64,7 @@ from litellm.llms.base_llm.guardrail_translation.utils import (
 )
 from litellm.llms.openai.responses.guardrail_translation.tool_merge import merge_guardrailed_tools
 from litellm.responses.litellm_completion_transformation.custom_tools import without_malformed_tool_flags
+from litellm.responses.litellm_completion_transformation.tool_search import is_server_tool_search_tool
 from litellm.responses.litellm_completion_transformation.transformation import (
     LiteLLMCompletionResponsesConfig,
 )
@@ -570,7 +571,12 @@ class OpenAIResponsesHandler(BaseTranslation):
         )
         scanned_tools: Final = tuple(without_malformed_tool_flags(tool) for tool in original_tools)
         flattened_tool_groups: Final = tuple(
-            form.chat_tools for form in LiteLLMCompletionResponsesConfig.responses_tools_to_chat_forms(scanned_tools)
+            () if is_server_tool_search_tool(tool) else form.chat_tools
+            for tool, form in zip(
+                scanned_tools,
+                LiteLLMCompletionResponsesConfig.responses_tools_to_chat_forms(scanned_tools),
+                strict=True,
+            )
         )
         extracted: Final = self._extract_guardrail_inputs(
             data, input_data, flattened_tool_groups, skip_system=skip_system

tests/unit/llms/openai/responses/test_openai_responses_guardrail_handler.py

@@ -3216,6 +3216,24 @@ class TestOpenAIResponsesHandlerNamespaceTools:
             "apply_patch",
         ]
 
+    @pytest.mark.asyncio
+    async def test_a_function_only_guardrail_keeps_the_tool_search_tool_it_never_scans(self):
+        data: Final = _codex_request("hi")
+        data["tools"] = [{"type": "tool_search"}, {**data["tools"][0], "defer_loading": True}]
+        expected_tools: Final = copy.deepcopy(data["tools"])
+        scanned: Final[list[list[dict]]] = []
+
+        def keep_functions(tools):
+            scanned.append(copy.deepcopy(tools))
+            return [tool for tool in tools if tool["type"] == "function"]
+
+        result: Final = await OpenAIResponsesHandler().process_input_messages(
+            data, ToolEditingGuardrail(edit=keep_functions, guardrail_name="test")
+        )
+
+        assert result["tools"] == expected_tools
+        assert [tool["type"] for tool in scanned[0]] == ["function"]
+
     @pytest.mark.asyncio
     async def test_appending_guardrail_keeps_namespace_and_adds_tool(self):
         data = _codex_request("hi")