{"version":1,"protocol":"x402","x402Version":2,"scheme":"exact","network":"eip155:8453","asset":"USDC","assetAddress":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","payTo":"0xfD2af2efFAF08877a98A3a02F7ee28D8191A3952","facilitator":"https://facilitator.payai.network","openapi":"https://x402-precheck.w0arvg81zlgf.workers.dev/openapi.json","mcp":"https://x402-precheck.w0arvg81zlgf.workers.dev/mcp","serverJson":"https://x402-precheck.w0arvg81zlgf.workers.dev/.well-known/mcp/server.json","agentCard":"https://x402-precheck.w0arvg81zlgf.workers.dev/.well-known/agent-card.json","resources":["https://x402-precheck.w0arvg81zlgf.workers.dev/v1/precheck"],"endpoints":[{"url":"https://x402-precheck.w0arvg81zlgf.workers.dev/v1/precheck","method":"GET","price":"$0.002","network":"eip155:8453","asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","payTo":"0xfD2af2efFAF08877a98A3a02F7ee28D8191A3952","scheme":"exact","mimeType":"application/json","tags":["x402","preflight","payments","safety","validation"],"description":"Check an x402 payment challenge BEFORE your agent pays (0.002 USDC per check via x402; free trial 1024 checks/IP/UTC day). Give an endpoint URL (fetched unpaid, never paid) or paste a 402 challenge. Validates x402 version, scheme, network (CAIP-2, testnet flag), canonical USDC asset, amount sanity, payTo format/EIP-55 checksum/zero address, EIP-712 domain, payment window, facilitator reachability and scheme/network support, optional maxPriceUsd / expectPayTo / expectNetwork policy, and PayAI Bazaar listing match. Returns per-check pass/warn/fail and a verdict: looks_ok, review or do_not_pay. Informational; invalid input and failed checks are not charged.","input":{"query":{"type":"object","properties":{"url":{"type":"string","description":"x402 endpoint URL to probe (public http/https). Fetched unpaid; never paid."},"challenge":{"type":["string","object"],"description":"Alternative to url: the 402 challenge itself (JSON body, or the base64 PAYMENT-REQUIRED header value). Takes precedence over url."},"method":{"type":"string","enum":["GET","POST"],"default":"GET","description":"HTTP method used to probe url"},"maxPriceUsd":{"type":"string","description":"Policy: fail options priced above this many USD (USDC)"},"expectPayTo":{"type":"string","description":"Policy: fail options whose payTo differs from this address"},"expectNetwork":{"type":"string","description":"Policy: fail options not on this network (CAIP-2, e.g. eip155:8453)"},"facilitator":{"type":"string","description":"Facilitator base URL to test (https). Default: PayAI (mainnet) / x402.org (testnet)."},"compareDirectory":{"type":"string","enum":["true","false"],"default":"true","description":"Compare live terms with the PayAI Bazaar listing (url mode)"}}}},"outputExample":{"verdict":"looks_ok","recommendedAccept":0,"summary":{"pass":14,"warn":0,"fail":0,"info":1},"accepts":[{"index":0,"network":"eip155:8453","networkName":"Base","isCanonicalUsdc":true,"priceUsd":0.01,"payTo":"0x…"}],"checks":[{"id":"accepts[0].payTo","status":"pass","message":"valid address, checksum OK"}]}}],"instructions":"x402 v2, exact scheme, USDC on eip155:8453. Unpaid GET returns 402 with PAYMENT-REQUIRED. Invalid input returns 400 before payment. Failed checks are not charged. Free trial: 1024 unpaid checks per IP per UTC day (HTTP and MCP share the bucket). After that, pay 0.002 USDC per check with x402. Global free cap 10000/day; trial auto-off if this service reaches 20000 requests/day.","disclosure":"Built and operated with AI assistance (an autonomous agent experiment); a human owner reviews it."}