Idempotency key reused - Vaquill AI


Code	`idempotency_key_reused`
HTTP status	`422`
Retryable	No
Python	`vaquill.IdempotencyKeyReusedError`
TypeScript	`IdempotencyKeyReusedError`

What it means

You sent an Idempotency-Key that was already used with a different request.

What to do

Use a fresh key for each distinct request. Reuse a key only when you resend the identical request.

Example response

The detail text is illustrative and can differ by endpoint. retryAfterSeconds appears only on a 429 or 503 that carries a Retry-After header.

{
  "type": "https://www.vaquill.ai/docs/errors/idempotency_key_reused",
  "title": "Idempotency key reused",
  "status": 422,
  "detail": "Idempotency key was used with a different request",
  "code": "idempotency_key_reused",
  "retryable": false,
  "requestId": "3f2b8c1e-5a7d-4e9b-9c34-0d6a1b2f7e58"
}

In the SDKs

The Python SDK raises IdempotencyKeyReusedError and the TypeScript SDK raises IdempotencyKeyReusedError. Both expose code, retryable, the request id and the retry hint. See Error codes for the full table and attribute names.

Last modified on October 29, 2026