{"uid":"cap_zb1sFYzYcQoKa_7If-4yP","slug":"ethereum-address-type-token-standard-inspector-3547f727","name":"Ethereum Address Type & Token Standard Inspector","description":"Identify what lives at a Ethereum address: wallet (EOA, including EIP-7702 delegation) or contract, which token standard it implements (ERC-20, ERC-721, ERC-1155), name and symbol, upgradeable-proxy implementation and admin, smart-wallet proxies, bytecode size, nonce and ETH balance.","url":"https://onchaincheck.dev/eth/contract?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["address"],"properties":{"address":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$","description":"Any address on Ethereum"}},"additionalProperties":false}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"kind":"ERC-20 token","name":"USD Coin","chain":"eth","proxy":{"admin":"0x807a96288A1A408dBC13DE2b1d087d10356395d2","upgradeable":true,"implementation":"0x43506849D7C04F9138D1A2050bbF3A0c054402dd"},"symbol":"USDC","address":"0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48","decimals":6,"standards":{"erc20":true,"erc165":false,"erc721":false,"erc1155":false},"isContract":true,"totalSupply":"48016325237.499139","bytecodeBytes":2186,"nativeBalance":"0"}},"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_-lIo0GxGYNO4jxuKl3mxk","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":"Identifies whether an Ethereum address is a wallet or contract, detects token standards (ERC-20/721/1155), retrieves name/symbol/decimals, and surfaces proxy/upgrade details, bytecode size, nonce, and ETH balance.","exampleAgentPrompt":"Can you check what lives at Ethereum address 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 — is it a wallet or contract, what token standard it uses, and whether it's an upgradeable proxy?","exampleUseCases":[{"title":"Token contract due diligence","prompt":"I found this contract address 0xdAC17F958D2ee523a2206206994597C13D831ec7 — can you tell me if it's an ERC-20, what its name and symbol are, and whether it's hiding behind an upgradeable proxy?"},{"title":"Verify wallet vs contract before transfer","prompt":"Before I send funds, can you confirm whether 0x3fC91A3afd70395Cd496C647d5a6CC9D4B2b7FAD is a plain wallet or a smart contract on Ethereum?"},{"title":"Smart wallet proxy inspection","prompt":"I need to know the implementation address and proxy admin for the contract at 0xCB1355ff08Ab38bBCE60111F1bb2B784bE25D7e5 on Ethereum — is it an upgradeable proxy and what standard does it follow?"}],"resultDescription":"A JSON object containing: address kind label (e.g. 'ERC-20 token', 'EOA', 'smart wallet'), chain identifier, token name and symbol, decimals, total supply, isContract boolean, token standard flags (erc20/erc165/erc721/erc1155), proxy details (upgradeable boolean, implementation address, admin address), bytecode size in bytes, nonce, and native ETH balance.","failureModes":["Invalid address format (not matching 0x + 40 hex chars) returns a validation error","Non-existent or never-used address returns isContract false with zero balance and nonce","Network timeout or RPC node unavailability may cause 5xx errors","Address with no deployed bytecode classified as EOA even if it was previously a contract (selfdestruct)","EIP-7702 delegated wallets may appear ambiguous between EOA and contract classification on older indexers"],"whenToPreferThis":"Choose this endpoint when you need a comprehensive, single-call identity snapshot of any Ethereum address — covering wallet vs contract classification, token standard detection, proxy architecture, and balance — rather than making multiple separate RPC calls. Ideal for due-diligence workflows, token metadata enrichment, or pre-transfer safety checks where you need to know exactly what you're dealing with before proceeding.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-29T12:41:09.826Z","isFirstParty":false,"canonicalSlug":"ethereum-address-type-token-standard-inspector-3547f727"}