{"uid":"cap_G-7-eglC2ctW5VMICaLC3","slug":"busker-signature-verifier-cb52fc83","name":"Busker Signature Verifier","description":"Verify EVM signatures offline: EIP-191 personal messages, EIP-712 typed data, and x402/EIP-3009 payment authorizations (paste a raw Payment-Signature header) — recovers the signing wallet, checks it against an expected address, and reports the authorization's amount, payee and validity window. No chain reads.","url":"https://workbot1.oddsys.org/verify-sig?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"domain":{"type":"object","description":"Explicit EIP-712 domain { name, version, chainId, verifyingContract } for a non-USDC token."},"address":{"type":"string","description":"Expected signer; when given the response carries a matches boolean."},"message":{"type":"string","description":"Plain message that was signed with personal_sign (EIP-191)."},"network":{"type":"string","description":"CAIP-2 network for authorization mode (default eip155:8453 = USDC on Base)."},"signature":{"type":"string","description":"0x-prefixed 65-byte signature."},"typedData":{"type":"object","description":"EIP-712 payload { domain, types, primaryType, message } exactly as signed."},"authorization":{"type":"object","description":"EIP-3009 TransferWithAuthorization fields { from, to, value, validAfter, validBefore, nonce } (the x402 payload.authorization object)."},"paymentHeader":{"type":"string","description":"Raw base64 value of an x402 Payment-Signature / X-Payment header; decoded and verified in one step."}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","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":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_4CSqD6wW4MKBOeku_NFmY","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Verifies EVM signatures offline — EIP-191 personal messages, EIP-712 typed data, and x402/EIP-3009 payment authorizations — recovering the signing wallet and reporting authorization details without any blockchain reads.","exampleAgentPrompt":"Can you verify this EVM signature for me — check if wallet 0xAbC...123 actually signed this EIP-191 personal message '0xdeadbeef...' with signature 0x1a2b...ff, and tell me if it matches?","exampleUseCases":[{"title":"Validate incoming x402 payment header","prompt":"I just received this x402 Payment-Signature header from a client — can you decode it and tell me whether the signature is valid, who signed it, how much USDC they authorized, who the payee is, and whether the validity window is still open?"},{"title":"Recover signer from EIP-712 typed data","prompt":"I have an EIP-712 typed data payload that was signed by a user and a 65-byte signature starting with 0x — can you recover which wallet address signed it and check if it matches 0xDef...456?"},{"title":"Verify EIP-3009 payment authorization offline","prompt":"Before I process this USDC transfer, can you verify this EIP-3009 authorization — the from address is 0xAaa...111, to is 0xBbb...222, value is 5000000, with these validAfter and validBefore timestamps and this nonce — and confirm the signature matches the from address?"}],"resultDescription":"Returns the recovered signer wallet address, a boolean indicating whether it matches the expected address (if provided), and — for EIP-3009/x402 authorizations — the authorized amount, payee address, and validity window (validAfter/validBefore timestamps). All computation is done off-chain with no blockchain reads.","failureModes":["Invalid or malformed signature (not 65 bytes, incorrect 0x prefix) returns an error","Mismatched EIP-712 domain or types cause wrong signer recovery without explicit error","Expired or not-yet-valid authorization windows are reported but not treated as hard errors","Malformed base64 paymentHeader fails to decode","Missing required fields for the chosen verification mode (e.g. authorization without signature) cause validation errors","Wrong network/chainId in domain causes incorrect recovery for non-USDC tokens"],"whenToPreferThis":"Choose this endpoint when you need offline, no-RPC EVM signature verification — especially for x402/EIP-3009 payment headers that need to be validated server-side before processing. It handles all three EVM signature flavors (EIP-191, EIP-712, EIP-3009) in a single call and can parse raw base64 Payment-Signature headers directly. Prefer it over on-chain verification when latency, cost, or RPC availability is a concern, and when the authorization data is fully contained in the signed payload.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-12T00:36:06.798Z","isFirstParty":false,"canonicalSlug":"busker-signature-verifier-cb52fc83"}