tool_execution.cancelled

One entry per generated result, each with a hydrated file. Present on tool_execution.succeeded and tool_execution.awaiting_approval.

Standard error body returned with every non-2xx response (the default response of every operation). The HTTP status code conveys the error class; this body carries the details:

• 400 invalid request, 401 missing or invalid API key, 403 not permitted (e.g. plan or add-on required, see requirement), 404 not found, 409 conflict, 429 rate limited or out of credits, 5xx server error.

Common code values include invalid_request, invalid_api_key, not_authorized, not_found, insufficient_credits, and rate_limited. Always branch on code (and requirement.type when present) rather than parsing message.