{"protocolVersion":"0.3.0","name":"x402check","description":"Call before paying any x402 tool. Trust-check the seller URL: is it reachable, is the 402 legit, what payTo/price does it demand, and has payTo or price drifted. Returns ok|caution|avoid + that tool's history only. Budget guard and compare helpers for agents. Paid per URL. Not a wallet OFAC/drainer scanner.","url":"https://x402check.dev/preflight","preferredTransport":"HTTP+JSON","version":"0.2.2","documentationUrl":"https://x402check.dev/docs","iconUrl":"https://x402check.dev/assets/icon.svg","provider":{"organization":"x402check","url":"https://x402check.dev"},"capabilities":{"streaming":false,"pushNotifications":false,"stateTransitionHistory":false},"defaultInputModes":["application/json","text/plain"],"defaultOutputModes":["application/json"],"supportedInterfaces":[{"url":"https://x402check.dev/preflight","protocolBinding":"https://x402.org/http+json","protocolVersion":"2"},{"url":"https://x402check.dev/mcp","protocolBinding":"https://modelcontextprotocol.io/streamable-http","protocolVersion":"2025-03-26"}],"skills":[{"id":"preflight_one","name":"Preflight one x402 tool","description":"Trust-check one absolute https x402 seller URL before you pay it. Use for: is this endpoint safe/legit; verify payTo; detect price or wallet drift; check uptime; validate 402 payment requirements; budget guard before signing USDC on Base; debug a failing 402.","tags":["x402","trust","preflight","safety","payTo","verify","uptime","scam-check","budget-guard"],"examples":["GET https://x402check.dev/preflight?url=https://seller.example/api (pay $0.002 first)","Is https://seller.example/x402 safe to pay?","Verify payTo for this x402 tool before settle","Has this seller changed price or wallet?","Is this x402 endpoint down?"],"inputModes":["application/json"],"outputModes":["application/json"]},{"id":"verify_payto","name":"Verify x402 payTo","description":"Extract and verify the receiving wallet (payTo) from a seller's live 402 challenge, with history of wallet rotations. Use before signing a USDC transfer.","tags":["x402","payTo","verify","wallet","Base","USDC"],"examples":["What payTo address does this x402 tool demand?","Compare payTo to my allowlist before settle"],"inputModes":["application/json"],"outputModes":["application/json"]},{"id":"preflight_batch","name":"Compare / batch preflight x402 tools","description":"Trust-check up to 25 seller URLs in one request. Charged per URL (N × unit) in a single Exact settlement. Use when comparing candidates, picking cheapest/most reliable, or screening Bazaar hits before paying.","tags":["x402","trust","batch","compare","cheapest","reliable"],"examples":["POST https://x402check.dev/preflight {\"urls\":[\"https://a.example\",\"https://b.example\"]}","Which of these paid APIs is safest and cheapest?"],"inputModes":["application/json"],"outputModes":["application/json"]}],"securitySchemes":{"x402":{"type":"apiKey","in":"header","name":"PAYMENT-SIGNATURE","description":"x402 Exact payment proof after 402 PAYMENT-REQUIRED challenge"}},"security":[{"x402":[]}]}