{"uid":"cap_chQQatUXXTDVw9yJrPL30","slug":"agentindex-x402-wallet-balance-15d9c86c","name":"AgentIndex x402 Wallet Balance","description":"Read native coin and USDC balances for any EVM wallet on Base, Ethereum, Polygon, Arbitrum or Optimism, with atomic amounts and current block. No RPC key or account. Try GET /wallet-balance/sample.","url":"https://x402.agentindex.world/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","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","required":["address"],"properties":{"address":{"type":"string","description":"EVM wallet address (0x followed by 40 hexadecimal characters)."},"network":{"enum":["base","ethereum","polygon","arbitrum","optimism"],"type":"string","description":"EVM network to read; aliases and CAIP-2 identifiers are also accepted."}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","required":["address","network","block_number","native","usdc"],"properties":{"usdc":{"type":"object"},"native":{"type":"object"},"address":{"type":"string"},"network":{"type":"object"},"block_number":{"type":"integer"},"x402_receipt":{"type":"object"}}}}}}},"responseSchema":{"type":"json","example":{"usdc":{"balance":1.25,"contract":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","decimals":6,"balance_atomic":"1250000"},"native":{"symbol":"ETH","balance":0.001,"balance_wei":"1000000000000000"},"address":"0xb3F32bdfe8D07825BC0D7387295aB1D7559BA69d","network":{"key":"base","name":"Base","caip2":"eip155:8453"},"block_number":51500000}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.001","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":"$0.001/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_xTor0bPCjOxDOcQjuyjaV","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns native token (ETH/MATIC/etc.) and USDC balances for any EVM wallet address on supported chains","exampleAgentPrompt":"What's the current ETH and USDC balance for wallet address 0xb3F32bdfe8D07825BC0D7387295aB1D7559BA69d on Base?","exampleUseCases":[{"title":"Pre-payment fund check for agent","prompt":"Before I send a transaction, can you check if wallet 0xb3F32bdfe8D07825BC0D7387295aB1D7559BA69d has at least 5 USDC on Base?"},{"title":"Multi-chain portfolio snapshot","prompt":"What are the ETH and USDC balances for 0xb3F32bdfe8D07825BC0D7387295aB1D7559BA69d on Ethereum mainnet right now?"},{"title":"Arbitrum treasury monitoring","prompt":"Check the current native token and USDC balance for our treasury wallet 0xb3F32bdfe8D07825BC0D7387295aB1D7559BA69d on Arbitrum."}],"resultDescription":"Returns a JSON object containing the wallet address, network metadata (key, name, CAIP-2 identifier), block number at time of query, native token balance (symbol, human-readable balance, and wei amount), and USDC balance (human-readable balance, atomic balance, decimals, and contract address).","failureModes":["Invalid wallet address format (not 0x + 40 hex chars) returns validation error","Unsupported network name returns enum error","Payment failure (insufficient USDC for x402 micropayment) blocks the call","Network RPC unavailability may return timeout or 503","Address with no on-chain activity returns zero balances but succeeds"],"whenToPreferThis":"Use this endpoint when an AI agent needs to read live on-chain wallet balances across Base, Ethereum, Polygon, Arbitrum, or Optimism without running its own node. It's ideal for pre-transaction fund checks, portfolio reads, or treasury monitoring, especially within x402/MPP pay-per-call agent workflows where the cost ($0.0001 USDC) is negligible. Prefer this over generic blockchain RPCs when you want a structured JSON response with both native and USDC balances in one call.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-29T07:39:16.343Z","isFirstParty":false,"canonicalSlug":"agentindex-x402-wallet-balance-15d9c86c"}