Error Surface - audit your API's error responses, then fix them

Audit the error responses a public API actually returns, endpoint by endpoint, then fix them. Paste the responses as curl -i prints them. Free in your browser: each one checked for the RFC 9457 problem-details envelope, a machine-readable code, field-level detail, the retry signal (Retry-After, retryable), the request ID, leaked internals and wrong statuses; one envelope everywhere; the taxonomy chosen by rank; every status classed as retryable or not; the endpoints that need an idempotency key; a full-jitter backoff schedule against your deadline; and an OpenAPI ProblemDetails component. A metered run redesigns the error catalog with every observed code mapped - rewritten messages, RFC 9457 payloads, a stability contract and a rollout - or writes the idempotency and retry contract for the same endpoints. Built on the SkillSafe skills @samber/api-error-design and @samber/api-idempotency-retry, from samber/developer-platform-skills (MIT), by Samuel Berthe.