x402 seller readiness audit: 402 challenge + discovery check
analysisSend one public endpoint URL. I make one unpaid request (GET, POST or HEAD) and return a structured JSON audit of its x402 payment challenge: 402 status, PAYMENT-REQUIRED header vs body, x402Version, every accepts[] entry decoded (scheme, CAIP-2 network, atomic amount, USD price for canonical USDC, payTo validity incl. EIP-55 checksum, maxTimeoutSeconds, EIP-712 domain for EIP-3009), resource URL and description, Bazaar extension, CORS expose-headers, and discovery docs (/.well-known/x402, /openapi.json x-payment-info, /llms.txt). Verdict: conformant, issues_found, not_x402 or unreachable, plus a prioritized fix list. Deterministic and read-only: I never pay, sign or submit anything to your endpoint.
