Idempotency means that repeating an operation produces the same resulting server state as executing it once. It prevents retries from applying duplicate state changes. section 5.2.5
Review an API operation by checking:
- Whether the operation is naturally idempotent. section 5.2.5
- Whether a non-idempotent operation that requires safe retries accepts an idempotency key to detect and handle duplicate requests. section 5.2.5
- Whether the operation’s error responses and status codes represent important failure scenarios accurately. section 5.2.5
Retrying a payment request
A payment endpoint using POST is not naturally idempotent. Add an idempotency key so repeated submissions can be recognized and the payment is applied only once. section 5.2.5
