Agent/examples/application_reference/tools/verify_fact.py

class FactVerifier:
    def __init__(self, artifacts) -> None:
        self.artifacts = artifacts
        self.calls = 0

    async def verify(
        self,
        *,
        question: str,
        root_trace_id: str,
        uid: str | None,
    ):
        self.calls += 1
        return self.artifacts.put(
            artifact_id="fact:framework-definition",
            version="1",
            kind="evidence.fact",
            root_trace_id=root_trace_id,
            uid=uid,
            content={
                "question": question,
                "answer": "An agent framework supplies reusable execution contracts.",
                "source": "reference-fixture",
            },
        )