HTTP errors you should not retry blindly
2026-03-21 · Using the API
401 and 422 will not succeed if you send the same request again. 503 and 429 might.
401 means the key is missing, wrong, or revoked. Fix the key. 402 means you are out of credits. 404 on a result means that id is not yours or it has expired.
422 means the options or the alert URL failed validation. Change the body. Retrying is pointless.
429 means too many concurrent calls or too many unfinished tasks, or an alert test inside the 10 second cooldown. Honour Retry-After.
503 solver_unavailable means the credit was returned. Retry the image later with backoff. A 200 with error set is not a 503. It is a finished, free, bad image.
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