rohitg00/ai-engineering-from-scratch · error · ValueError

Messages API response must be an object

Error message

Messages API response must be an object

What it means

Error "Messages API response must be an object" thrown in rohitg00/ai-engineering-from-scratch.

Source

Thrown at certifications/claude/lessons/30-developer-application-capstone/code/main.py:68

    def create_message(self, payload: dict[str, Any]) -> dict[str, Any]:
        body = json.dumps(payload).encode("utf-8")
        request = urllib.request.Request(
            self.endpoint,
            data=body,
            method="POST",
            headers={
                "content-type": "application/json",
                "anthropic-version": ANTHROPIC_VERSION,
                "x-api-key": self._api_key,
            },
        )
        try:
            with self._opener(request, timeout=self.timeout_seconds) as response:
                decoded = json.loads(response.read().decode("utf-8"))
        except urllib.error.HTTPError as error:
            raise RuntimeError(f"Messages API returned HTTP {error.code}") from None
        if not isinstance(decoded, dict):
            raise ValueError("Messages API response must be an object")
        return decoded


def build_live_order_request(request: str, model: str) -> dict[str, Any]:
    """Build an inspectable wire payload with the same bounded lookup contract."""
    return {
        "model": model,
        "max_tokens": 128,
        "system": (
            "You are a bounded order-status router. Use lookup_order only when "
            "the user supplies an exact public order ID. Never claim execution."
        ),
        "messages": [{"role": "user", "content": request}],
        "tools": [
            {
                "name": "lookup_order",
                "description": "Read one visible order status. Never changes order state.",
                "input_schema": {

View on GitHub (pinned to 39ea8a1c6d)

When it happens

Trigger: Thrown at certifications/claude/lessons/30-developer-application-capstone/code/main.py:68 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of rohitg00/ai-engineering-from-scratch@39ea8a1c6d (2026-08-26). Data as JSON: /api/errors/b9f8ecd78b98d71d. Report an issue: GitHub.