fix(search): validate client type for search and asearch modes

litellm/search/main.py

@@ -15,6 +15,7 @@ from litellm._logging import verbose_logger
 from litellm.constants import request_timeout
 from litellm.litellm_core_utils.litellm_logging import Logging as LiteLLMLoggingObj
 from litellm.llms.base_llm.search.transformation import BaseSearchConfig, SearchResponse
+from litellm.llms.custom_httpx.http_handler import AsyncHTTPHandler, HTTPHandler
 from litellm.llms.custom_httpx.llm_http_handler import BaseLLMHTTPHandler
 from litellm.types.utils import SearchProviders
 from litellm.utils import ProviderConfigManager, client, filter_out_litellm_params
@@ -233,6 +234,17 @@ def search(
         client: Final = kwargs.get("client", None)
         _is_async: Final = kwargs.pop("asearch", False) is True
 
+        if _is_async:
+            if client is not None and not isinstance(client, AsyncHTTPHandler):
+                raise ValueError(
+                    f"client must be an instance of AsyncHTTPHandler for asynchronous search, got {type(client)}"
+                )
+        else:
+            if client is not None and not isinstance(client, HTTPHandler):
+                raise ValueError(
+                    f"client must be an instance of HTTPHandler for synchronous search, got {type(client)}"
+                )
+
         # Validate query parameter
         if not isinstance(query, (str, list)):
             raise ValueError(f"query must be a string or list of strings, got {type(query)}")

tests/test_litellm/llms/base_llm/search/test_base_search_transformation.py

@@ -450,3 +450,26 @@ class TestSearchHTTPErrorHandling:
                     search_provider="tavily",
                     api_key="tvly-testkey",
                 )
+
+    def test_sync_search_rejects_async_client(self) -> None:
+        """Verify that passing an AsyncHTTPHandler to synchronous search raises a clear exception."""
+        async_client = AsyncHTTPHandler()
+        with pytest.raises(Exception, match="client must be an instance of HTTPHandler"):
+            litellm.search(
+                query="test query",
+                search_provider="tavily",
+                api_key="tvly-testkey",
+                client=async_client,
+            )
+
+    @pytest.mark.asyncio
+    async def test_async_search_rejects_sync_client(self) -> None:
+        """Verify that passing a sync HTTPHandler to asynchronous search raises a clear exception."""
+        sync_client = HTTPHandler()
+        with pytest.raises(Exception, match="client must be an instance of AsyncHTTPHandler"):
+            await litellm.asearch(
+                query="test query",
+                search_provider="tavily",
+                api_key="tvly-testkey",
+                client=sync_client,
+            )