{"uid":"cap_-NzlTwPcgCEOxeaP-zDcV","slug":"base-calldata-decoder-692e5b95","name":"Base Calldata Decoder","description":"Self-computed Base onchain toolkit for AI agents: ERC-20 safety scan, manipulation-resistant TWAP price oracle, gas/fee oracle, calldata decoder, token/address/contract intel, wallet approval-risk audit, and batch token triage — all computed live from raw Base chain, no third-party data.","url":"https://x402-data-api.bodhinindustries.workers.dev/decode","method":"GET","headers":{},"bodySchema":{"type":"object","properties":{"to":{"type":"string","description":"Optional target contract address; its bytecode presence is surfaced as context."},"data":{"type":"string","description":"Raw calldata hex (0x + 4-byte selector + ABI-encoded args). Required unless txHash is given."},"txHash":{"type":"string","description":"Base mainnet transaction hash; its input calldata is fetched and decoded. Required unless data is given."}}},"responseSchema":{"type":"object","properties":{"args":{"type":"array","items":{"type":"object","properties":{"name":{"type":"string","description":"arg name"},"type":{"type":"string","description":"solidity type"},"value":{"type":"string","description":"decoded value as string"}}},"description":"decoded [{name,type,value}] (or null)"},"matched":{"type":"boolean","description":"true if a signature was resolved"},"selector":{"type":"string","description":"4-byte function selector"},"collision":{"type":"boolean","description":"true if multiple 4byte signatures share this selector"},"signature":{"type":"string","description":"full function signature (or null)"},"computedAt":{"type":"string","description":"ISO-8601 timestamp"},"functionName":{"type":"string","description":"resolved function name (or null)"},"selectorRegistry":{"type":"string","description":"4byte.directory"},"thirdPartyDataUsed":{"type":"boolean","description":"true — selector labels from 4byte; arg decoding is local"},"candidateSignatures":{"type":"array","items":{"type":"string"},"description":"all 4byte candidates, canonical first"}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","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":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_Mu11aM0hSQBdqRY4M3qDM","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Decodes raw EVM calldata hex or a Base mainnet transaction hash into a human-readable function signature, name, selector, and typed arguments using local ABI decoding plus 4byte.directory signature lookup.","exampleAgentPrompt":"Can you decode this Base transaction calldata for me — 0xa9059cbb000000000000000000000000ab5801a7d398351b8be11c439e05c5b3259aec9000000000000000000000000000000000000000000000000016345785d8a0000 — and tell me what function it's calling and what the arguments are?","exampleUseCases":null,"resultDescription":"Returns the resolved function name, full Solidity signature, 4-byte selector, decoded argument list (name, Solidity type, value), a boolean indicating whether the signature was matched, a collision flag if multiple 4byte signatures share the selector, all candidate signatures from 4byte.directory, and an ISO-8601 timestamp of when the computation was performed.","failureModes":["Calldata too short or malformed hex — selector cannot be extracted, matched=false returned","Unknown selector not in 4byte.directory — functionName and signature are null, matched=false","Selector collision — multiple candidate signatures returned, collision=true, ambiguous decoding","Invalid transaction hash or tx not found on Base mainnet — error or empty response","ABI decoding mismatch — signature resolves but arguments fail to decode against the candidate signature"],"whenToPreferThis":"Use this endpoint when you need to decode raw EVM calldata or a Base mainnet transaction's input data into human-readable form, especially when you want local ABI decoding (no third-party data for arg values) combined with 4byte.directory signature resolution. Prefer this over Etherscan-style decoders when you need programmatic structured output (typed name/value pairs) rather than a UI, or when you want to verify what a transaction actually called before signing or analyzing it.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-13T18:44:15.236Z","isFirstParty":false}