{"uid":"cap_GuGOnDWgBZcKNXNFBbQ5B","slug":"foundry-x402-preflight-and-base-contract-facts-61bbd961","name":"Foundry: x402 Preflight and Base Contract Facts","description":"Pay-per-call data for agents: check x402 sellers before paying them, and read Base contracts' proxy, owner and privileged powers straight from the chain.","url":"https://minty-sprout.onrender.com/v1/extract?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"input":{"type":"string","maxLength":8000}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.03","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":"$0.03/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.03","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.03","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_ROH65BU5Ixg2vNchCfQMX","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.03","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Checks x402 payment endpoints before you pay them and reads Base smart contract metadata (proxy, owner, privileged roles) directly from the chain.","exampleAgentPrompt":"Before I pay that x402 endpoint at https://api.example.com/v1/data, can you run a preflight check on it and also pull the proxy and owner info for the Base contract at 0xAbC123...?","exampleUseCases":[{"title":"Preflight check before x402 payment","prompt":"I'm about to call an x402-gated API at https://some-seller.onrender.com/v1/generate — can you verify it looks legitimate and tell me if it's safe to pay before I send any USDC?"},{"title":"Inspect Base contract ownership","prompt":"Who owns the smart contract at 0x1234abcd...5678 on Base, and is it behind a proxy? I want to know the owner and any privileged roles before interacting with it."},{"title":"Agent safety check on new x402 vendor","prompt":"I found a new x402 data vendor at https://new-vendor.example.com/api — run a preflight on it and check if the contract address they gave me has any unusual admin powers on Base."}],"resultDescription":"Returns x402 seller metadata (whether the endpoint is a valid x402 seller, pricing, payment details) and/or Base contract facts (proxy implementation address, contract owner, privileged role addresses) read directly from the chain.","failureModes":["Invalid or unreachable x402 URL returns an error or empty seller info","Contract address not found on Base returns no results","Malformed input string causes a parsing error","Rate limiting or server errors from the underlying render.com deployment","Contract is not a proxy so proxy fields are null or absent"],"whenToPreferThis":"Use this endpoint when an AI agent needs to safely vet an x402 payment endpoint before sending funds, or when you need quick on-chain facts about a Base smart contract (owner, proxy, privileged roles) without setting up your own RPC connection. Prefer this over generic blockchain explorers when you want a single pay-per-call, agent-friendly API that combines x402 seller checks and Base contract introspection in one call.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-11-01T06:57:42.453Z","isFirstParty":false,"canonicalSlug":"foundry-x402-preflight-and-base-contract-facts-61bbd961"}