diff --git a/src/google/adk/tools/openapi_tool/openapi_spec_parser/rest_api_tool.py b/src/google/adk/tools/openapi_tool/openapi_spec_parser/rest_api_tool.py
index 5f83548980..7fdc693d2f 100644
--- a/src/google/adk/tools/openapi_tool/openapi_spec_parser/rest_api_tool.py
+++ b/src/google/adk/tools/openapi_tool/openapi_spec_parser/rest_api_tool.py
@@ -571,6 +571,7 @@ def __repr__(self):
 
 async def _request(**request_params) -> httpx.Response:
   async with httpx.AsyncClient(
-      verify=request_params.pop("verify", True)
+      verify=request_params.pop("verify", True),
+      timeout=request_params.pop("timeout", httpx.Timeout(600.0)),
   ) as client:
     return await client.request(**request_params)