{"uid":"cap_tcjbVbCVo4nhf4KgSuFnN","slug":"x402-payment-preflight-checker-38ecb8f0","name":"x402 Payment Preflight Checker","description":"Public data and utility APIs paid per call in USDC on Base (x402). No accounts, no API keys. 174 routes: crypto/equity data, onchain reads, DNS/email/security intel, geo/weather, x402 payment diagnostics, dev utilities and more.","url":"https://anibalb.duckdns.org/x402/x402-payment-preflight?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","properties":{}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"url":"https://example.com/api","score":100,"checks":[{"ok":true,"name":"returns_402"}],"status":402,"accepts":[{"amount":"1000","network":"eip155:8453","price_usd":0.001,"payTo_checksum_ok":true}],"payable":true,"verdict":"payable"}},"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":"unknown","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_s76lCRItTrkwWAxIGXXYm","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":"Checks whether a given HTTP endpoint is properly configured to accept x402 micropayments and returns a diagnostic verdict with payment details","exampleAgentPrompt":"Run an x402 payment preflight check using a GET method to see if that endpoint is properly configured to accept micropayments — I want to know the verdict, the score, and what payment address it expects.","exampleUseCases":[{"title":"Debugging a misconfigured x402 API","prompt":"My x402 endpoint doesn't seem to be accepting payments correctly — can you run a preflight diagnostic on it using a GET request and tell me which checks are failing and what the verdict is?"},{"title":"Pre-call payability check for an agent","prompt":"Before my agent tries to pay and call that endpoint, can you do a preflight check with a GET to confirm it's actually payable and find out the exact USDC amount and wallet address it expects on Base?"},{"title":"Auditing a new x402-enabled route","prompt":"I just added a new paid route to my API — can you run an x402 preflight on it via GET to verify it returns a proper 402 status, passes all compliance checks, and has a valid payTo address?"}],"resultDescription":"Returns a JSON object with the target URL, a compliance score (0-100), an array of named diagnostic checks (each with pass/fail status), the HTTP status code received, accepted payment terms (amount, network, USD price, checksum validity), a boolean payability flag, and an overall verdict string (e.g. 'payable').","failureModes":["Target endpoint is unreachable or times out — checks array will reflect failed connectivity","Endpoint does not return a 402 status — returns_402 check will fail and verdict will be non-payable","Malformed payment header on target — payTo_checksum_ok will be false","Invalid or unsupported HTTP method supplied — request rejected by schema validation","Target endpoint is on an unsupported network — accepts array may be empty"],"whenToPreferThis":"Use this endpoint when you need to programmatically verify that an x402-gated API endpoint is correctly configured before attempting a micropayment — ideal for agent pre-flight logic, developer debugging, or automated compliance audits of x402 routes. Prefer this over manually inspecting 402 headers when you want a structured, scored diagnostic report.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-31T18:42:04.535Z","isFirstParty":false,"canonicalSlug":"x402-payment-preflight-checker-38ecb8f0"}