{"uid":"cap_cBmq14RLZFGgjIV9QY4MD","slug":"evm-decode-signature-212db6d3","name":"EVM Decode Signature","description":"Reverse a 4-byte function selector, an event topic hash, or raw calldata into its human-readable signature using the 4byte database, with collisions resolved so the real signature (the oldest registered) is returned first and the attacker-registered lookalikes are flagged. Parameter types are parsed out.","url":"https://payai.agentstools.dev/evm/decode-signature?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","required":[],"properties":{"input":{"type":"string","description":"Raw calldata or hex; the first 4 bytes are taken as the selector (alternative to selector/topic0)"},"topic0":{"type":"string","description":"Event topic0 hash (0x + 64 hex)"},"selector":{"type":"string","description":"4-byte function selector (0x + 8 hex)"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","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":{"p10Cents":"0.3000","medianCents":"0.3000","p90Cents":"0.3000","minCents":"0.3000","maxCents":"0.3000","p95Cents":"0.3000","sampleCount":1,"varies":false,"failureChargeRate":1},"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.003/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_5L-In54oDwRZC2DhB46Yt","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Reverse a 4-byte function selector, event topic0 hash, or raw calldata into a human-readable Solidity signature using the 4byte database, with collision resolution and parameter type parsing.","exampleAgentPrompt":"What Solidity function does the selector 0xa9059cbb map to? Decode it using the 4byte database and give me the full signature with parameter types, flagging any collision lookalikes.","exampleUseCases":null,"resultDescription":"Returns the canonical human-readable Solidity function or event signature (oldest registered entry first), the parsed parameter types, and any collision entries (attacker-registered lookalikes) flagged separately.","failureModes":["Selector or topic0 not found in 4byte database — returns empty or not-found response","Invalid hex format for selector/topic0/input — returns validation error","Selector is ambiguous with multiple unresolvable collisions — multiple results returned with collision flags","Fewer than 4 bytes provided in raw calldata — cannot extract selector"],"whenToPreferThis":"Use this endpoint when you need to decode an unknown EVM function selector, event topic hash, or raw calldata into a human-readable Solidity signature, especially when collision safety matters. Prefer this over raw 4byte.directory queries when you need collision resolution (real vs attacker-registered signatures) and structured parameter type parsing in a single call.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-12T00:42:04.780Z","isFirstParty":false,"canonicalSlug":"evm-decode-signature-212db6d3"}