OK

The request was rejected before it was applied — either a field failed validation (validation_failed, with error.fields naming each one), or the request could not be read at all (bad_request: malformed JSON, an unknown field, a missing parameter, or an unparseable path or query value).

No credential was presented, or the one presented was rejected.

The credential is valid but is not allowed to call this operation.

Rate limit exceeded

An unexpected error. Safe to retry with backoff; use an idempotency key where the operation accepts one.