{"uid":"cap_qfjnm47tQizoLMFfX0pyG","slug":"foundry-x402-seller-due-diligence-c199cac5","name":"Foundry x402 Seller Due Diligence","description":"x402 seller due diligence: everything in x402-preflight PLUS on-chain proof of real demand (USDC actually received by the seller's payTo in the last 24h: payments, distinct payers, volume) and a Bazaar listing-truth audit (is this URL listed, does the listed price match what it charges). Reveals dead, fake or mispriced sellers before payment.","url":"https://minty-sprout.onrender.com/v1/x402-due-diligence?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"input":{"type":"string","maxLength":8000,"description":"URL of a paid x402 endpoint to investigate before paying it"}}},"responseSchema":{"type":"json","example":{"url":"https://x402-preflight.nextill-pos.workers.dev/v1/preflight","issues":[],"method":"GET","seller":{"bazaar":{"checked":true,"this_url_listed":true,"listed_price_usd":0.003,"price_matches_listing":true},"issues":[],"pay_to":"0xB3cDDccEe6B150c8efFD55B961afc0Ecefe7f247","network":"eip155:8453","onchain":{"payments":34,"window_hours":24,"usdc_received":6.18,"distinct_payers":8,"pay_to_is_contract":false}},"status":402,"options":[{"issues":[],"pay_to":"0xB3cDDccEe6B150c8efFD55B961afc0Ecefe7f247","scheme":"exact","network":"eip155:8453","verdict":"ok","price_usd":0.003,"asset_symbol":"USDC"}],"verdict":"ok","latency_ms":1001,"x402_version":2,"bazaar_extension":true}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_iAs-fQCyMFoMAYbeStlQj","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Performs comprehensive pre-payment due diligence on an x402 paid endpoint, combining preflight checks, on-chain USDC payment history, and Bazaar listing verification to detect dead, fake, or mispriced sellers.","exampleAgentPrompt":"Before I pay that x402 endpoint at https://x402-preflight.nextill-pos.workers.dev/v1/preflight, run a full due diligence check on it — I want to see if the seller has real on-chain payment history, whether the price matches its Bazaar listing, and whether there are any issues I should know about.","exampleUseCases":[{"title":"Fraud check before paying unknown API","prompt":"I found this x402 endpoint at https://some-new-api.example.com/data that charges $0.01 per call — can you do a full due diligence check on it before I start paying? I want to know if it's legitimate, has real users, and whether the price matches what's listed in Bazaar."},{"title":"Verifying seller activity for marketplace integration","prompt":"I'm building a tool that aggregates x402 APIs — before I include https://weather-paid.workers.dev/forecast in my catalog, can you check how many distinct payers have used it in the last 24 hours and whether its Bazaar listing price is accurate?"},{"title":"Detecting dead or abandoned paid endpoint","prompt":"This x402 endpoint https://old-seller.onrender.com/api/report used to work but I'm not sure if it's still active — can you investigate it and tell me if there's been any real USDC received recently and if there are any issues with its configuration?"}],"resultDescription":"Returns a JSON object with a top-level verdict (ok or issues found), the endpoint's x402 method and version, a list of any detected issues, payment options with per-option verdicts and prices, on-chain stats for the seller's payTo address (payment count, distinct payers, USDC volume over 24h, whether the address is a contract), and a Bazaar listing audit (whether the URL is listed, the listed price, and whether it matches what the endpoint actually charges).","failureModes":["URL is unreachable or not an x402 endpoint — returns issues in the issues array","On-chain data unavailable if Base RPC is degraded — may return incomplete onchain stats","Bazaar listing not found — checked:true but this_url_listed:false","Seller payTo address has zero payments — reveals dead or new seller","Price mismatch detected — price_matches_listing:false in Bazaar section","Malformed input URL returns validation error"],"whenToPreferThis":"Choose this endpoint when you need the most thorough pre-payment check on an x402 seller, going beyond basic preflight (connectivity, scheme, pricing) to include on-chain proof that real USDC has actually flowed to the seller's address and a Bazaar marketplace listing audit. Prefer it over x402-preflight alone when dealing with unfamiliar sellers, high-value automation, or when building a catalog/aggregator that must filter out dead or fraudulent endpoints.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-11-01T06:57:40.318Z","isFirstParty":false,"canonicalSlug":"foundry-x402-seller-due-diligence-c199cac5"}