test_parse_does_not_duplicate_beta_header() — anthropic-sdk-python Function Reference

Source Code

tests/api_resources/beta/test_output_format_conversion.py lines 456–490

    def test_parse_does_not_duplicate_beta_header(self, client: Anthropic, respx_mock: MockRouter) -> None:
        """Verify .parse() doesn't duplicate structured-outputs beta if already present."""

        class DataModel(BaseModel):
            value: int

        respx_mock.post("/v1/messages?beta=true").mock(
            return_value=httpx.Response(
                200,
                json={
                    "id": "msg_123",
                    "type": "message",
                    "role": "assistant",
                    "model": "claude-sonnet-4-5",
                    "content": [{"text": '{"value": 42}', "type": "text"}],
                    "stop_reason": "end_turn",
                    "usage": {"input_tokens": 10, "output_tokens": 20},
                },
            )
        )

        with warnings.catch_warnings(record=True):
            warnings.simplefilter("always")
            client.beta.messages.parse(
                max_tokens=1024,
                messages=[{"role": "user", "content": "Test"}],
                model="claude-sonnet-4-5",
                output_format=DataModel,
                betas=["structured-outputs-2025-12-15"],
            )

        request = respx_mock.calls.last.request
        beta_header = request.headers["anthropic-beta"]
        # Should only appear once
        assert beta_header.count("structured-outputs-2025-12-15") == 1