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

# Idempotency

> Retry writes safely.

Send an `Idempotency-Key` header (up to 255 characters) on `POST /v1/disputes`, `POST /v1/disputes/{id}/review`, `POST /v1/cases` and the other case writes.

* A retry with the same key and the same body returns the first response, with `Idempotent-Replayed: true`.
* The same key with a different body returns `422 idempotency_conflict`.
* `external_reference` adds a second guard: one dispute or case per reference.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.