x402 Doctor

Why is my x402 endpoint broken? Diagnose and debug an x402 payment endpoint (or MCP server) when payments fail: checks the 402 challenge, accepts[] (network, payTo, amount, asset), resource URL, Solana settlement readiness, which wallets and agents can pay, Bazaar/OpenAPI discovery and the browser paywall. Returns every check with a fix hint. Read-only: never pays. Bulk: 1000 credits for $0.80 via

Open endpoint ↗

Price per call: $0.01
Chain: Base
Method: GET
Paid calls · 30 days: 5

Call it from code

This API is run by its own provider and paid directly through x402. We list it so you can find it; we don't route or hold the payment.

import { x402Client, wrapFetchWithPayment } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";

const client = new x402Client();
registerExactEvmScheme(client, { signer: agentAccount });

const pay = wrapFetchWithPayment(fetch, client);
const res = await pay("https://x402-doctor.fizzl.eu/api/v1/diagnose", { method: "GET" });
console.log(await res.json());

https://x402-doctor.fizzl.eu/api/v1/diagnose