{"uid":"cap_kakU_wrac16Rhb_WUnE-r","slug":"evm-calldata-transaction-decoder-x402-settlement-verifier-083ca64c","name":"EVM Calldata & Transaction Decoder / x402 Settlement Verifier","description":"Decode EVM calldata or a Base-mainnet transaction into human-readable form: function selector, matched signature, named args, plus ERC-20/USDC transfer events from the receipt — verify an x402 settlement receipt (tx hash in, payer/payee/amount out) in one call.","url":"https://workbot1.oddsys.org/decode-tx","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"data":{"type":"string","description":"0x-prefixed EVM calldata to decode (offline)."},"txHash":{"type":"string","description":"0x-prefixed Base-mainnet transaction hash — fetches, decodes, and lists ERC-20/USDC transfer events (x402 receipt verification)."}}},"responseSchema":null,"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_w7fi0C4nsWRWtyhUUuIKi","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":"Decodes a Base-mainnet transaction hash or raw EVM calldata into human-readable form — function selector, matched signature, named arguments, and ERC-20/USDC transfer events — and can verify an x402 payment settlement receipt in one call.","exampleAgentPrompt":"Can you decode this Base mainnet transaction for me — 0x4a3b...c9f2 — and tell me what function was called, what the arguments were, and whether it contains a USDC transfer so I can verify the x402 payment settlement?","exampleUseCases":[{"title":"Verify x402 payment receipt","prompt":"I need to confirm that this Base transaction 0xabc123...def456 is a valid x402 payment — can you decode it and tell me who the payer was, who the payee was, and how much USDC was transferred?"},{"title":"Debug smart contract call","prompt":"This transaction hash on Base — 0x7f1e...8d34 — was a failed contract interaction. Can you decode the calldata so I can see which function was called and what arguments were passed?"},{"title":"Audit USDC transfer events","prompt":"Pull the ERC-20 transfer events from Base tx 0x99ab...1234 and give me the full breakdown: token, sender, recipient, and amount — I need it for our payment reconciliation records."}],"resultDescription":"Returns the decoded function selector, matched ABI signature, named and typed arguments, and any ERC-20/USDC Transfer events found in the transaction receipt, including payer address, payee address, and USDC amount — all in structured, human-readable JSON.","failureModes":["Transaction hash not found on Base mainnet — returns 404 or not-found error","Calldata does not match any known ABI signature — selector returned but arguments may be unresolved","Transaction is pending/unconfirmed — receipt events unavailable","Malformed calldata or invalid hex — parsing error returned","Rate limit or payment failure for the $0.005 USDC per-call fee"],"whenToPreferThis":"Choose this endpoint when you need a single-call solution to decode Base-mainnet EVM calldata or verify an x402 payment settlement receipt — it combines calldata decoding and ERC-20 event extraction in one step, saving round trips. Prefer it over raw RPC calls when you need human-readable argument names and USDC transfer verification without setting up local ABI parsing infrastructure.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T00:40:11.857Z","isFirstParty":false}