fix(live): forward thinking config

Author: he-yufeng

src/google/adk/models/google_llm.py

@@ -453,6 +453,10 @@ async def connect(self, llm_request: LlmRequest) -> BaseLlmConnection:
             ' backend. Please use Vertex AI backend.'
         )
     llm_request.live_connect_config.tools = llm_request.config.tools
+    if llm_request.config.thinking_config is not None:
+      llm_request.live_connect_config.thinking_config = (
+          llm_request.config.thinking_config
+      )
     logger.debug('Connecting to live with llm_request:%s', llm_request)
     logger.debug('Live connect config: %s', llm_request.live_connect_config)
     async with self._live_api_client.aio.live.connect(

tests/unittests/models/test_google_llm.py

@@ -852,6 +852,36 @@ async def __aexit__(self, *args):
         )
 
 
+@pytest.mark.asyncio
+async def test_connect_forwards_thinking_config(gemini_llm, llm_request):
+  """Test that live sessions keep the request thinking_config."""
+  thinking_config = types.ThinkingConfig(thinking_budget=128)
+  llm_request.config.thinking_config = thinking_config
+  llm_request.live_connect_config = types.LiveConnectConfig()
+
+  mock_live_session = mock.AsyncMock()
+
+  with mock.patch.object(gemini_llm, "_live_api_client") as mock_live_client:
+
+    class MockLiveConnect:
+
+      async def __aenter__(self):
+        return mock_live_session
+
+      async def __aexit__(self, *args):
+        pass
+
+    mock_live_client.aio.live.connect.return_value = MockLiveConnect()
+
+    async with gemini_llm.connect(llm_request) as connection:
+      mock_live_client.aio.live.connect.assert_called_once()
+      call_args = mock_live_client.aio.live.connect.call_args
+      config_arg = call_args.kwargs["config"]
+
+      assert config_arg.thinking_config == thinking_config
+      assert isinstance(connection, GeminiLlmConnection)
+
+
 @pytest.mark.parametrize(
     (
         "api_backend, "