{"uid":"cap_HgdToBZ8CWyD3I41JX8hI","slug":"base-mainnet-eth-usdc-balance-lookup-34808620","name":"Base Mainnet ETH & USDC Balance Lookup","description":"Call when an agent needs Base mainnet ETH and USDC balances, tx_count, and a rough x402 affordability hint for one address. Send address as EIP-55 or all-lowercase 0x. Read-only eth_getBalance and USDC balanceOf on eip155:8453. No private key and no spend. Send JSON {\"address\":\"0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045\"}. Exact $0.003 USDC on Base. Try unpaid POST /v1/sandbox/base-balance first.","url":"https://agentshelf.syntexa.ch/v1/base-balance?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"address":{"type":"string","examples":["0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"],"description":"EVM address on Base mainnet (eip155:8453). Example: 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045. EIP-55 checksum or all one case. Returns eth_wei, eth, usdc_atomic, usdc, tx_count, and x402_hint. Read-only. No private key."}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","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":"$0.003/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_AFj38v2-s2FufJNAJgaZe","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns ETH balance, USDC balance, transaction count, and an x402 affordability hint for a given Base mainnet address","exampleAgentPrompt":"What are the ETH and USDC balances for 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Base mainnet, and does it have enough to cover x402 micropayments?","exampleUseCases":[{"title":"Pre-flight wallet funding check","prompt":"Before I trigger any paid API calls, check if 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 has enough ETH and USDC on Base to cover x402 fees."},{"title":"Portfolio snapshot for a Base address","prompt":"Give me the current ETH and USDC balances plus the transaction count for wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Base mainnet."},{"title":"Agent self-funding verification","prompt":"My agent wallet is 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 — can you check its Base mainnet USDC and ETH balances so I know if it needs topping up before the next run?"}],"resultDescription":"Returns a JSON object containing the address's ETH balance in both wei and decimal, USDC balance in both atomic units and decimal, the total transaction count (nonce), and an x402_hint boolean or affordability signal indicating whether the wallet has sufficient funds to make x402 micropayments on Base.","failureModes":["Invalid or malformed address returns a 400 error","Non-checksummed address that is ambiguous may be rejected","Network timeout or Base RPC node unavailability returns a 5xx error","Address with zero balance returns valid response with zeroed fields","Unsupported network addresses (non-Base) will not return correct results"],"whenToPreferThis":"Choose this endpoint when you specifically need on-chain Base mainnet (eip155:8453) ETH and USDC balances together with an x402 affordability hint in a single call. It is ideal for agents operating in the x402 payment ecosystem that need to verify wallet funding before initiating micropayments. Prefer it over generic blockchain explorers when you need a programmatic, structured JSON response including the x402_hint field.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-12T12:46:39.155Z","isFirstParty":false,"canonicalSlug":"base-mainnet-eth-usdc-balance-lookup-34808620"}