x402 test endpoint (GET) — failure injection with query params only. Query param failRate (0-1): the request fails with 500 BEFORE payment is taken, so you can test that your x402 client never treats a 5xx as paid and retries without double-paying.
| Network | Scheme | Amount | Pay To |
|---|---|---|---|
| Base | exact | $0.001000 USDC | 0xb92A...4029 |