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

packet root must be an object

Error message

packet root must be an object

What it means

Error "packet root must be an object" thrown in rohitg00/ai-engineering-from-scratch.

Source

Thrown at certifications/claude/lessons/03-prompting-and-task-decomposition/code/main.py:72

            errors.append("every evaluation case needs an expected behavior")
    return errors


def score_packet(packet: dict[str, Any]) -> dict[str, Any]:
    errors = validate_packet(packet)
    return {
        "passed": not errors,
        "errors": errors,
        "contractFields": len(set(packet.get("contract", {})) & CONTRACT_FIELDS) if isinstance(packet.get("contract"), dict) else 0,
        "caseCoverage": sorted({case.get("type") for case in packet.get("evaluationCases", []) if isinstance(case, dict)}),
        "stageCount": len(packet.get("stages", [])) if isinstance(packet.get("stages"), list) else 0,
    }


def load_packet(path: Path) -> dict[str, Any]:
    value = json.loads(path.read_text(encoding="utf-8"))
    if not isinstance(value, dict):
        raise ValueError("packet root must be an object")
    return value


if __name__ == "__main__":
    path = Path(__file__).parents[1] / "outputs" / "prompt-contract-packet.json"
    print(json.dumps(score_packet(load_packet(path)), indent=2))

View on GitHub (pinned to 39ea8a1c6d)

When it happens

Trigger: Thrown at certifications/claude/lessons/03-prompting-and-task-decomposition/code/main.py:72 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/a74bb67ffc23ee99. Report an issue: GitHub.