{"uid":"cap_Nr6qFPPNv80QaLdpUyjHe","slug":"x402-payment-channel-voucher-auditor-20c1a06d","name":"x402 Payment Channel Voucher Auditor","description":"Checks vouchers of a payment channel by computation only - nothing is ever claimed, redeemed or refunded. Signatures are verified cryptographically against the address each voucher claims to be signed by, in EIP-712 form when the typed data is supplied, otherwise as a plain message signature. Double spending is the expensive case and is checked in full: every voucher id occurring more than once is reported with all its occurrences and whether the duplicates agree on the amount. Sums are added up","url":"https://x402.halowerk.com/channel/audit?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"chain":{"type":"string","description":"Optional chain, needed only to read the on-chain state, as CAIP-2 such as eip155:8453."},"vouchers":{"type":"array","items":{"type":"object","required":["id","amount"],"properties":{"id":{"type":"string","description":"Voucher identifier."},"amount":{"type":"string","description":"Amount in the smallest unit, as a decimal string."},"expiry":{"type":"string","description":"Optional expiry as a unix timestamp in seconds."},"claimed":{"type":"boolean","description":"Whether the caller considers this voucher already claimed."},"message":{"type":"string","description":"The signed message, for a plain message signature."},"signature":{"type":"string","description":"The signature, 0x-prefixed."},"signed_by":{"type":"string","description":"Address that is claimed to have signed."},"typed_data":{"type":"object","description":"EIP-712 payload with domain, types, primaryType and message."}},"additionalProperties":false},"maxItems":200,"minItems":1,"description":"The vouchers to audit."},"deposited":{"type":"string","description":"Optional deposit in the smallest unit, used when the contract cannot be read."},"channel_id":{"type":"string","description":"Optional channel identifier as bytes32."},"channel_contract":{"type":"string","description":"Optional channel contract address."}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.006","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":"$0.006/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.006","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.006","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_9v55wP_sqGCVFDtDddNDj","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.006","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Cryptographically audits vouchers in a payment channel by verifying signatures and detecting double-spending, without redeeming or modifying any state.","exampleAgentPrompt":"Can you audit all the vouchers in this x402 payment channel for me — verify each signature against its claimed signer address using EIP-712 typed data, flag any duplicate voucher IDs with their amounts, and give me a total sum? I just want the analysis, no redemptions or claims.","exampleUseCases":[{"title":"Pre-settlement channel integrity check","prompt":"Before I close out this x402 payment channel, audit all the vouchers for me — check every signature is valid against the claimed signer, flag any double-spend attempts where the same voucher ID appears more than once, and tell me if the duplicates agree on the amount."},{"title":"Fraud detection on received vouchers","prompt":"I received a batch of x402 payment channel vouchers and I'm worried some might be fraudulent. Can you verify all the EIP-712 signatures and tell me if any voucher IDs are being reused or if any signatures don't match their claimed addresses?"},{"title":"Voucher sum reconciliation","prompt":"I need to reconcile the total value in my x402 payment channel — please audit all the vouchers, verify the cryptographic signatures, and add up the amounts so I know what the legitimate total is, flagging any duplicates along the way."}],"resultDescription":"Returns cryptographic verification results for each voucher including whether the signature is valid against the claimed signer address (in EIP-712 or plain message form), a report of all duplicate voucher IDs with every occurrence listed and whether duplicates agree on the amount, and a running total of all voucher amounts. No on-chain state is changed.","failureModes":["Invalid or malformed EIP-712 typed data causes signature verification failure","Missing voucher fields result in parsing errors","Vouchers with mismatched signer addresses are flagged as invalid signatures","Large batches of vouchers with many duplicates may increase computation time","Malformed input JSON returns a 400-level error"],"whenToPreferThis":"Use this endpoint when you need a pure cryptographic audit of payment channel vouchers with zero side effects — it never touches on-chain state, claims nothing, and redeems nothing. Prefer it over stateful settlement or claim endpoints when you want to validate integrity before committing, detect fraud in received vouchers, or reconcile channel amounts offline. Best when EIP-712 typed data is available for stronger signature verification, though plain message signatures are also supported.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-17T12:36:38.066Z","isFirstParty":false,"canonicalSlug":"x402-payment-channel-voucher-auditor-20c1a06d"}