fix(tools): guard set_model_response as a reserved MCP tool name

src/google/adk/tools/mcp_tool/mcp_tool.py

@@ -54,6 +54,7 @@
 # part of the ADK public API; consumers flip the env var, not the symbol.
 from .._gemini_schema_util import _to_gemini_schema
 from ..base_authenticated_tool import BaseAuthenticatedTool
+from ..set_model_response_tool import SET_MODEL_RESPONSE_FUNCTION_CALL_NAME
 from ..tool_context import ToolContext
 from ..transfer_to_agent_tool import transfer_to_agent
 from .mcp_session_manager import _http_debug_var
@@ -70,6 +71,7 @@
     REQUEST_EUC_FUNCTION_CALL_NAME,
     REQUEST_CONFIRMATION_FUNCTION_CALL_NAME,
     REQUEST_INPUT_FUNCTION_CALL_NAME,
+    SET_MODEL_RESPONSE_FUNCTION_CALL_NAME,
     transfer_to_agent.__name__,
 })
 

src/google/adk/tools/set_model_response_tool.py

@@ -39,6 +39,12 @@
 from .base_tool import BaseTool
 from .tool_context import ToolContext
 
+# Name the framework dispatches this tool under. Exposed as a module-level
+# constant (mirroring functions.py's REQUEST_*_FUNCTION_CALL_NAME) so other
+# modules -- e.g. the MCP reserved-name guard -- can refer to it without
+# hardcoding the literal.
+SET_MODEL_RESPONSE_FUNCTION_CALL_NAME = 'set_model_response'
+
 
 def _merge_json_schema_descriptions(
     target: dict[str, Any], source: dict[str, Any]
@@ -215,7 +221,7 @@ def set_model_response() -> str:
     self.func = set_model_response
 
     super().__init__(
-        name=self.func.__name__,
+        name=SET_MODEL_RESPONSE_FUNCTION_CALL_NAME,
         description=self.func.__doc__.strip() if self.func.__doc__ else '',
     )
 

tests/unittests/tools/mcp_tool/test_mcp_tool.py

@@ -343,6 +343,7 @@ def test_init_with_empty_description(self):
           "adk_request_credential",
           "adk_request_confirmation",
           "adk_request_input",
+          "set_model_response",
           "transfer_to_agent",
       ],
   )