> ## Documentation Index
> Fetch the complete documentation index at: https://circle-devdocs-test-ai-codegen-component.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Idempotent Requests

Circle APIs support
[idempotent requests](https://en.wikipedia.org/wiki/Idempotence), a type of
request method in which multiple executions of the same request have no effect.
You can safely retry API calls when things go wrong during a transaction, such
as a network connection issue.

An idempotency key is a unique value generated by the client, which the server
uses to recognize subsequent retries of the same request. To ensure a request is
idempotent, you must generate and provide an idempotency key formatted as a
[UUID version 4 format](https://en.wikipedia.org/wiki/Universally_unique_identifier).
Subsequent requests with the same `idempotencyKey` parameter value will produce
the same result as the initial request.

To quickly generate a UUID version 4 you can go to
[uuidgenerator.net](https://www.uuidgenerator.net/).