Idempotency key reuse

This page is the resolution target of the RFC 9457 type URI on every idempotency_key_reuse problem body: https://docs.get-exo.com/errors/idempotency_key_reuse. HTTP status: 422 Unprocessable Content.

{
  "type": "https://docs.get-exo.com/errors/idempotency_key_reuse",
  "title": "Idempotency key reuse",
  "status": 422,
  "detail": "This Idempotency-Key was already used with a different request body.",
  "code": "idempotency_key_reuse",
  "requestId": "req_9f2c41ab7d0e5c18",
  "suggestedAction": "Use a new Idempotency-Key for each distinct request."
}

Why it happens

A key is bound to the exact body it was first used with. Reusing it for different content is a client bug, and Exo refuses rather than replaying the wrong response or silently applying the new content. This is checked before the in-flight state, so it fires whether or not the original request has finished.

How to fix it

Generate one key per distinct request, and reuse it only for retries of that same request.
A UUID per logical operation is the usual pattern.

idempotency_in_flight
validation_error
Errors for the envelope and the full catalogue

Idempotency in flight

Internal error

⌘I

Start

Building with Exo

Platform

Idempotency key reuse

Why it happens

How to fix it

​Why it happens

​How to fix it

​Related

Why it happens

How to fix it

Related