Glossary
What is a idempotency?
Idempotencyn is idempotent when doing it twice has the same effect as doing it once. An idempotent signing request can be retried after a network failure without creating a second signature.
Networks fail. If your server does not hear back from a request, it must retry, but it cannot know whether the first attempt succeeded.
With an idempotency key, the retry returns the original request instead of starting a new one.