DDG Agent Checkout Conformance Audit
Pre-purchase audit of an agent-facing checkout flow: 402 challenge shape, payTo/asset correctness, extra.name, and receipt verifiability. POST with input JSON. $0.02 USDC per call on Base.
x402 verified · Verified on /v1/tx-smoke-test · $0.01 · $0.02 USDC/request · 1 endpoints / 1 tools · Tools · base network · x402 protocol
Discovery is free. Agents search the catalogue here. Payment happens on the listing 402, not on PayAPI.
url https://payapi.market/mcpHow to call this API
Every protected route returns HTTP 402 with x402 payment requirements. An agent pays the stated USDC amount on Base and retries with the payment header. No API keys, no accounts. Browse the marketplace or list your own API.