test_validation_error_with_invalid_response() — langchain Function Reference

Source Code

libs/langchain_v1/tests/unit_tests/agents/test_response_format.py lines 653–684

    def test_validation_error_with_invalid_response(self) -> None:
        """Test validation error with invalid response.

        Test that StructuredOutputValidationError is raised when tool strategy receives
        invalid response.
        """
        tool_calls = [
            [
                {
                    "name": "WeatherBaseModel",
                    "id": "1",
                    "args": {"invalid_field": "wrong_data", "another_bad_field": 123},
                },
            ],
        ]

        model = FakeToolCallingModel(tool_calls=tool_calls)

        agent = create_agent(
            model,
            [],
            response_format=ToolStrategy(
                WeatherBaseModel,
                handle_errors=False,  # Disable retry to ensure error is raised
            ),
        )

        with pytest.raises(
            StructuredOutputValidationError,
            match=r".*WeatherBaseModel.*",
        ):
            agent.invoke({"messages": [HumanMessage("What's the weather?")]})