{"uid":"cap_4ajNE272nWkGoMiQMk7a_","slug":"chain-contract-code-857d6db1","name":"chain-contract-code","description":"Is this address a contract? Bytecode size, EIP-1967 proxy implementation and EIP-7702 delegation. Default chain Base; prefix another: ethereum:, arbitrum:, optimism:, polygon:, bsc:. $0.01 per call.","url":"https://chain.intel.rallylive.ca/chain/code?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$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"],"type":"string"},"queryParams":{"type":"object","properties":{}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"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_Yz0ed2TWyRIL-DpmqjuKD","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":"Checks if an Ethereum-compatible address is a smart contract, returning bytecode size, EIP-1967 proxy implementation address, and EIP-7702 delegation info across multiple chains.","exampleAgentPrompt":"Is the address 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 a smart contract on Ethereum, and if it's a proxy, what's its implementation address?","exampleUseCases":[{"title":"Proxy implementation resolution for DeFi protocol","prompt":"Can you check if 0x7Fc66500c84A76Ad7e9c93437bFc5Ac33E2DDaE9 on Ethereum is a proxy contract and tell me what implementation address it points to?"},{"title":"EOA vs contract detection before funds transfer","prompt":"Before I send funds to 0x3fC91A3afd70395Cd496C647d5a6CC9D4B2b7FAD on Base, can you confirm whether it's a plain wallet or a smart contract?"},{"title":"EIP-7702 delegation check on Arbitrum","prompt":"Check the address 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Arbitrum — is it an EOA, a contract, or does it have an EIP-7702 delegation set up?"}],"resultDescription":"Returns whether the address has deployed bytecode (is a contract), the size of that bytecode, the EIP-1967 proxy implementation address if applicable, and EIP-7702 delegation target if present — all for the specified chain (defaults to Base).","failureModes":["Invalid or malformed address returns an error","Unsupported chain prefix returns an error","Address not found on the specified chain returns empty/null bytecode size","Network timeout or RPC unavailability causes failure","Missing required input parameter returns a 400-level error"],"whenToPreferThis":"Use this endpoint when you need to determine whether an address is a smart contract vs an EOA, or when you need to resolve proxy contract implementation addresses (EIP-1967) or EIP-7702 delegation targets across EVM chains including Base, Ethereum, Arbitrum, Optimism, Polygon, and BSC. Prefer this over general blockchain explorers when you need programmatic, structured data for agent workflows at low cost ($0.01/call).","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-02T12:40:52.234Z","isFirstParty":false,"canonicalSlug":"chain-contract-code-857d6db1"}