Errors and retries

Every answer has the same envelope. A refusal adds error.code and a requestId to quote to All Out. Branch on the HTTP status and error.code, never on the message text.

Only 503 and a timeout are worth retrying unchanged, with the same Idempotency-Key. Every other code needs something to change first.

HTTP	error.code	Do
400	INVALID_REQUEST	Fix the request.
401	UNAUTHORIZED	Get a new token.
403	PARTNER_DISABLED	Your account is suspended. Contact All Out.
404	NOT_FOUND	Check the id and the route.
409	REFERENCE_CONFLICT, PAYMENT_REFERENCE_CONFLICT, IDEMPOTENCY_CONFLICT	Use a new reference or key, or check your references.
409	AVAILABILITY_NOT_CONFIRMED, AVAILABILITY_EXPIRED	Do not hold. Release a hold already placed, then make a new request.
409	INVALID_PAYMENT_TRANSITION, CANCELLATION_NOT_ALLOWED	Read the booking and check its state.
413	INVALID_REQUEST	Send a smaller body or picture.
422	PAYMENT_AMOUNT_MISMATCH	Release. Never hold a different amount.
422	UNPRICEABLE	Contact All Out.
429	RATE_LIMITED	Wait the seconds in Retry-After.
503	UNAVAILABLE	Retry with the same key, or read the booking.