{"uid":"cap_crCPXLf_BzI_pG7jNtAP1","slug":"code402-ethereum-address-nonce-lookup-3d512c0f","name":"code402 Ethereum Address Nonce Lookup","description":"Deterministic compliance verification (IBAN, sanctions, onchain address) with XDR-1 signed receipts, plus Ethereum chain-data endpoints. Paid per call via x402 on Base (USDC).","url":"https://verify.code402.dev/v1/chain/nonce/%7Baddress%7D?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object"}}},"output":{"type":"object","required":["type","example"],"properties":{"type":{"type":"string","const":"json"},"example":{"result":"string","network":"ethereum-mainnet"}}}}},"responseSchema":{"type":"json","example":{"result":"chain data","network":"ethereum"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.5","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"registry","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":"$0.5/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.5","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.5","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_2loanhqLdbH21Oxce7GDW","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.5","costPer":"request","priority":0,"asset":"0x833589fcd6edb6e08f4c7c32d4f71b54bda02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Fetches the current transaction nonce for a given Ethereum address via the code402 chain-data API, paid per call via x402 on Base USDC.","exampleAgentPrompt":"What's the current transaction nonce for the Ethereum address 0xAbC123...456 — I need it before signing my next transaction?","exampleUseCases":[{"title":"Pre-signing nonce check for DApp","prompt":"Before I sign this transaction, can you look up the current nonce for my Ethereum address 0x1234567890abcdef1234567890abcdef12345678 so I don't accidentally reuse or skip a sequence number?"},{"title":"Auditing wallet transaction count","prompt":"I want to know how many transactions the Ethereum wallet 0xDeAdBeEf0000000000000000000000000000dEaD has sent in total — can you fetch its current nonce?"},{"title":"Debugging stuck pending transaction","prompt":"My transaction seems stuck — can you check the on-chain nonce for address 0xaBcD1234EfGh5678 so I can figure out whether there's a gap in my transaction sequence?"}],"resultDescription":"Returns a JSON object containing the current transaction nonce for the queried Ethereum address, along with the network name (e.g. 'ethereum') and a result field confirming the chain data. This allows callers to determine the next valid transaction sequence number for the address.","failureModes":["Invalid or malformed Ethereum address returns an error response","Payment not fulfilled via x402 results in HTTP 402 Payment Required","Network unavailability or node errors may return 500-level responses","Address with no on-chain history may return nonce of 0, which is valid but could be misinterpreted"],"whenToPreferThis":"Choose this endpoint when you need a quick, pay-per-call lookup of an Ethereum address's current nonce without setting up your own node or RPC infrastructure. It is especially useful for agents that occasionally need on-chain sequence data without maintaining persistent blockchain connections, and where the x402 micropayment model on Base USDC is acceptable.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-03T00:39:58.663Z","isFirstParty":false,"canonicalSlug":"code402-ethereum-address-nonce-lookup-3d512c0f"}