{"uid":"cap_edzh2vbbWy_quQ-5QjwAU","slug":"x402-wallet-balance-lookup-59a0f8ee","name":"x402 Wallet Balance Lookup","description":"Native and (optional) ERC-20 token balance for a wallet address across major EVM chains (base, ethereum, polygon, arbitrum, optimism)","url":"https://agentx402pay.com/api/wallet-balance?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":{"chain":{"type":"string","description":"Chain to query: base, ethereum, polygon, arbitrum, optimism (default base)"},"token":{"type":"string","description":"Optional ERC-20 token contract address to also check"},"address":{"type":"string","description":"EVM wallet address (0x...)"}}}},"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_Srzcq0vFyrrUYmmPKeFFh","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 native and optional ERC-20 token balances for an EVM wallet address across major chains (Base, Ethereum, Polygon, Arbitrum, Optimism)","exampleAgentPrompt":"What's the ETH balance of wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Ethereum, and also check how much USDC (contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48) it holds?","exampleUseCases":[{"title":"Pre-transaction funding check","prompt":"Before I send this transaction, check if wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 has enough ETH on Base to cover it."},{"title":"DeFi portfolio snapshot","prompt":"Pull the USDC balance (contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48) for wallet 0xAb5801a7D398351b8bE11C439e05C5B3259aeC9B on Arbitrum — I want to know what's sitting there."},{"title":"Multi-chain wallet monitoring","prompt":"Check the native token balance on Polygon for wallet 0x742d35Cc6634C0532925a3b8D4C9C6E1f3d9A1eB and let me know if it's below 1 MATIC."}],"resultDescription":"Returns the native token balance (e.g. ETH, MATIC) for the specified wallet address on the requested chain, plus an optional ERC-20 token balance if a contract address is provided. Balances are returned as numeric values with token denominations.","failureModes":["Invalid or malformed wallet address (non-0x format) returns an error","Unsupported chain name returns an error — only base, ethereum, polygon, arbitrum, optimism are valid","Invalid ERC-20 contract address returns an error or empty token balance","Network/RPC timeout may cause transient failures","Payment failure (insufficient USDC) blocks the request"],"whenToPreferThis":"Choose this endpoint when you need a simple, paid-per-call balance lookup for an EVM wallet without managing your own RPC infrastructure. Ideal for agents that need to verify wallet funding before transactions, monitor balances across chains, or enrich wallet data. Prefer this over self-hosted RPC calls when you want a managed, multi-chain abstraction at low cost. Use the sibling x402 Multi-Chain RPC endpoint if you need raw JSON-RPC flexibility beyond balance lookups.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-20T12:39:33.244Z","isFirstParty":false,"canonicalSlug":"x402-wallet-balance-lookup-59a0f8ee"}