{"uid":"cap_xjKb3uPUv9MqXgOQIszhw","slug":"agent-data-tools-eth-balance-lookup-by-wallet-address-fd196b66","name":"Agent Data Tools: ETH Balance Lookup by Wallet Address","description":"Native ETH balance (eth_getBalance) of any 0x wallet address on Optimism at the latest block, in wei and in ETH. Use to check whether a wallet can pay gas or a transfer; for ERC-20 tokens use op_token_balance, for all holdings at once use wallet_portfolio. A malformed address is rejected with 400, uncharged.","url":"https://agent-data-tools.revmesh2074.workers.dev/op/balance?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","required":["address"],"properties":{"address":{"type":"string","description":"0x wallet or contract address"}}},"responseSchema":{"type":"object","properties":{"block":{"type":"number"},"chain":{"type":"string"},"symbol":{"type":"string"},"address":{"type":"string"},"balance":{"type":"string"},"chainId":{"type":"number"},"balanceWei":{"type":"string"}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USD","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_X9qiDnBtVjWHHHFHqzXqE","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":"Returns the native ETH (or chain-native token) balance of a given 0x wallet or contract address on a supported EVM chain","exampleAgentPrompt":"What's the current ETH balance for wallet address 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045? Give me both the human-readable balance and the raw Wei amount, and tell me which chain and block it was read from.","exampleUseCases":[{"title":"DeFi agent portfolio snapshot","prompt":"Check the native ETH balance for wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 — I want to know exactly how much ETH it holds right now, in both ETH and Wei."},{"title":"Smart contract ETH holdings audit","prompt":"How much ETH is currently held by the contract at address 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48? I need the balance and the block number it was read at."},{"title":"Wallet balance monitoring alert","prompt":"Fetch the on-chain ETH balance for address 0x71C7656EC7ab88b098defB751B7401B5f6d8976F so I can check if it's dropped below a threshold since last time."}],"resultDescription":"Returns a JSON object with the wallet address, human-readable ETH balance (as a decimal string), raw balance in Wei, the chain name (e.g. Optimism), chain ID (e.g. 10), the native token symbol (e.g. ETH), and the block number at which the balance was read.","failureModes":["Invalid or malformed 0x address returns an error response","Address with no activity may return a balance of 0 rather than an error","Network or RPC node issues may cause timeouts or temporary failures","Unsupported chain IDs may not be resolved correctly","Payment failure (x402) results in no charge and no data returned"],"whenToPreferThis":"Use this endpoint when you need a quick, cheap ($0.001 USDC) on-chain native token balance lookup for any EVM-compatible wallet or contract address without setting up your own RPC node or API key. It covers Base, Ethereum, Arbitrum, Optimism, and Polygon. Prefer this over full portfolio endpoints when you only need the native balance and not ERC-20 token holdings.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-30T06:46:03.984Z","isFirstParty":false,"canonicalSlug":"agent-data-tools-eth-balance-lookup-by-wallet-address-fd196b66"}