Errors

The public API uses stable HTTP status codes and error codes. SDK callers receive FabHubApiError for non-2xx responses.

Common statuses

• 400 invalid request or validation error
• 401 missing, invalid, expired, or revoked credential
• 403 missing scope, plan gate, or IP allowlist denial
• 404 resource not found
• 409 idempotency conflict
• 429 rate limit exceeded
• 500 server error

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Client guidance

Treat 401 and 403 as configuration or permission problems, not retryable failures. Treat 429 as retryable only after the advertised retry window. Use idempotency keys on writes before retrying transport failures.