X-Request-Id header; include it when you contact support.
code is a stable, machine readable string you can switch on. message is for people and can change. request_id matches the X-Request-Id header.
Status codes
Handling errors
Check the status first, thencode. Retry 429 and 5xx with backoff, and use an Idempotency-Key on POST /v1/printjobs so a retry cannot print twice (see Rate limits and idempotency). Fix the request for any other 4xx.
state becomes error and stateMessage holds the reason from the operating system. Watch for printjob.error in webhooks.