> ## Documentation Index
> Fetch the complete documentation index at: https://docs.nozlerouting.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Error codes, status semantics, and request IDs

> Canonical Nozle API error shape with error_code, message, details, and request_id, plus HTTP status code semantics for validation, auth, and rate limits.

All errors return a canonical shape with `error_code`, `message`,
optional `details`, and `request_id` (always set, useful in
support requests). Status codes follow standard HTTP semantics:
400 for validation errors, 403 for auth, 422 for infeasibility,
429 for rate limits, 500 for unexpected failures.