{"uid":"cap_U3176YiCYn2qvbT4IzqSo","slug":"x402-preflight-api-a3d3253d","name":"x402 Preflight API","description":"Deterministically checks a payable endpoint before an agent spends money.","url":"https://x402-preflight-api.onrender.com/api/v1/preflight?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","properties":{"url":{"type":"string","description":"Absolute HTTP(S) endpoint to inspect."},"maxPriceUsd":{"type":"string"},"maxLatencyMs":{"type":"integer"},"inspectOpenApi":{"type":"boolean"}}},"responseSchema":{"type":"json","format":"json","example":{"safety":{"safe":true},"target":"https://api.example.com/paid","reasons":["Valid x402 offer detected"],"service":"x402-preflight","verdict":"buy","checkedAt":"2026-08-09T01:35:00.000Z"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","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":"down","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_G8uL9CNh9aNx8LtCJ24kj","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Deterministically checks a payable (x402) endpoint to assess safety, price, and latency before an agent commits funds.","exampleAgentPrompt":"Before you pay for that endpoint at https://api.example.com/paid, run a preflight check on it — make sure it's safe, costs under $0.05, and responds within 2000ms.","exampleUseCases":[{"title":"Safe-to-buy check before agent payment","prompt":"Before calling https://api.weather-data.io/premium, preflight it to confirm it's safe and that the price is under $0.02 — only proceed if it passes."},{"title":"Latency-gated endpoint validation","prompt":"Check if https://api.imagegen.com/generate is a legitimate x402 endpoint and that it responds in under 1500 milliseconds before I let my agent pay for it."},{"title":"Budget-capped API discovery verification","prompt":"I found a new paid API at https://data.marketfeed.io/realtime — can you preflight it to see if it's safe, inspect its OpenAPI spec, and confirm the price is within $0.10?"}],"resultDescription":"Returns a JSON object with a safety assessment (safe: true/false), an overall verdict (e.g. 'buy' or 'skip'), a list of human-readable reasons explaining the verdict, the target URL inspected, a service label, and the UTC timestamp of the check.","failureModes":["Target URL is unreachable or returns non-402 response — verdict may be 'skip' with reasons citing missing x402 offer","Price exceeds maxPriceUsd threshold — verdict returns 'skip' with price mismatch reason","Latency exceeds maxLatencyMs — verdict returns 'skip' with latency reason","Malformed or non-HTTPS URL input — likely returns validation error","Target endpoint returns invalid or unparseable x402 payment header — safety flagged as false"],"whenToPreferThis":"Use this endpoint whenever an AI agent is about to spend money on an x402-payable API and needs a deterministic safety gate. It is the right choice when you want to enforce price caps, latency budgets, or safety checks before committing USDC, and when you need a structured buy/skip verdict rather than raw HTTP inspection. Prefer this over generic HTTP probing when the target is specifically an x402 endpoint and you want payment-aware validation.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-14T01:29:00.212Z","isFirstParty":false,"canonicalSlug":"x402-preflight-api-a3d3253d"}