fix tool config parsing with empty tools list

autogen/oai/gemini.py

@@ -124,7 +124,7 @@ def __init__(self, **kwargs):
 
         Args:
             api_key (str): The API key for using Gemini.
-                credentials (google.auth.credentials.Credentials): credentials to be used for authentication with vertexai.
+            credentials (google.auth.credentials.Credentials): credentials to be used for authentication with vertexai.
             google_application_credentials (str): Path to the JSON service account key file of the service account.
                 Alternatively, the GOOGLE_APPLICATION_CREDENTIALS environment variable
                 can also be set instead of using this argument.
@@ -647,9 +647,13 @@ def _to_vertexai_tool_config(tool_config, tools):
                 func_calling_config_params["mode"] = VertexAIToolConfig.FunctionCallingConfig.Mode[
                     tool_config["function_calling_config"]["mode"]
                 ]
-                # if func_calling_config_params["mode"] == VertexAIToolConfig.FunctionCallingConfig.Mode.ANY:
-                #    # The function names are not yet known when parsing the OAI_CONFIG_LIST
-                #    func_calling_config_params["allowed_function_names"] = [tool["function_name"] for tool in tools]
+                if (
+                    (func_calling_config_params["mode"] == VertexAIToolConfig.FunctionCallingConfig.Mode.ANY)
+                    and (len(tools) > 0)
+                    and all(["function_name" in tool for tool in tools])
+                ):
+                    # The function names are not yet known when parsing the OAI_CONFIG_LIST
+                    func_calling_config_params["allowed_function_names"] = [tool["function_name"] for tool in tools]
                 vertexai_tool_config = VertexAIToolConfig(
                     function_calling_config=VertexAIToolConfig.FunctionCallingConfig(**func_calling_config_params)
                 )

test/oai/test_gemini.py

@@ -280,6 +280,32 @@ def test_vertexai_tool_config(gemini_client):
     ), "Function calling allowed function names is not converted correctly"
 
 
+@pytest.mark.skipif(skip, reason="Google GenAI dependency is not installed")
+def test_vertexai_tool_config_no_functions(gemini_client):
+
+    tools = []
+
+    tool_config = {"function_calling_config": {"mode": "ANY"}}
+
+    expected_tool_config = VertexAIToolConfig(
+        function_calling_config=VertexAIToolConfig.FunctionCallingConfig(
+            mode=VertexAIToolConfig.FunctionCallingConfig.Mode.ANY,
+        )
+    )
+
+    converted_tool_config = GeminiClient._to_vertexai_tool_config(tool_config, tools)
+
+    converted_mode = converted_tool_config._gapic_tool_config.function_calling_config.mode
+    expected_mode = expected_tool_config._gapic_tool_config.function_calling_config.mode
+    converted_allowed_func = converted_tool_config._gapic_tool_config.function_calling_config.allowed_function_names
+    expected_allowed_func = expected_tool_config._gapic_tool_config.function_calling_config.allowed_function_names
+
+    assert converted_mode == expected_mode, "Function calling mode is not converted correctly"
+    assert (
+        converted_allowed_func == expected_allowed_func
+    ), "Function calling allowed function names is not converted correctly"
+
+
 # Test error handling
 @patch("autogen.oai.gemini.genai")
 @pytest.mark.skipif(skip, reason="Google GenAI dependency is not installed")