Correct idempotency (cached retry)
Compliant · GET /api/x402/idempotent-retry · Happy Path
Caches the result by payment id, so retrying the same payment returns the cached 200 without charging twice.
Explanation
Demonstrates correct idempotency: the server caches the result by payment id, so a retried request returns the same cached 200 and an Idempotent-Replay marker without charging the buyer twice. This is the safe way to handle network retries. Note that this is server-side idempotency keyed on the payment, which is distinct from edge/CDN caching: the paid response is still private and no-store, so a shared cache never serves it to a different client (see the Edge / CDN Controls category).
What to watch
A second call with the same payment returns Idempotent-Replay: true and does not re-settle.
Facilitator
Settled against the live Radius testnet facilitator (https://facilitator.testnet.radiustech.xyz). A valid payment runs a real /verify and /settle on-chain.
Metadata
- Status: Compliant
- Method: GET
- Price: 0.0001 (100 atomic)
- Responsible party: No fix needed