{"uid":"cap_aMRrbvL909UmZPqLBa04o","slug":"delx-commerce-evm-nonce-replace-check-a0b6ff7b","name":"Delx Commerce — EVM Nonce Replace Check","description":"Pay-per-result APIs for agents. No signup. Exact price. Verifiable delivery. USDC on Base + Solana via x402.","url":"https://commerce.delx.ai/api/v1/x402/evm-nonce-replace-check?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"pending_nonces":{"type":"array","items":{"type":"integer"},"maxItems":256,"description":"Pending Nonces supplied to EVM Nonce Replace Check; used only for this bounded calculation and processed in memory without retention."},"proposed_nonce":{"type":"integer","description":"Proposed Nonce supplied to EVM Nonce Replace Check; used only for this bounded calculation and processed in memory without retention."}}},"responseSchema":{"type":"json","example":{"result":{"proposed_nonce":11,"targets_pending":true},"schema":"delx/util-evm-nonce-replace-check/v1","status":"pass","evidence":{"retained":false,"input_sha256":"a3ab4cbc105327ec6bf99174fcfd83de2a8605ff927d8cd849aed39cba23d03e","external_calls":0},"operation":"evm_preflight:evm_nonce_replace_check"}},"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_D51k9VQMandBu-yoVr8ro","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":"Checks whether a proposed EVM transaction nonce targets any pending (stuck) nonces, enabling safe nonce replacement decisions before transaction submission.","exampleAgentPrompt":"Check if proposed nonce 11 would replace any of my pending EVM transactions with nonces [8, 9, 10] — I want to know if it's safe to use before I broadcast a replacement.","exampleUseCases":[{"title":"Unsticking a pending EVM transaction","prompt":"I have stuck pending transactions with nonces 5, 6, and 7 on EVM — check if using proposed nonce 6 would target one of those so I can safely replace it."},{"title":"Preflight check before gas-bumped resend","prompt":"Before I rebroadcast with a higher gas price, verify that my proposed nonce 42 actually targets one of my stuck pending nonces [40, 41, 42] so I don't accidentally skip a slot."},{"title":"Agent transaction queue management","prompt":"My agent has pending nonces [100, 101, 103] queued up — does proposed nonce 101 target any of them? I need to know before deciding whether to replace or cancel."}],"resultDescription":"Returns a JSON object containing the proposed nonce value, a boolean flag indicating whether it targets any pending nonce (targets_pending), a status field ('pass'), and an evidence object with a SHA256 hash of the inputs and confirmation that no data was retained and no external calls were made.","failureModes":["Input array exceeds 256 items (maxItems constraint violated)","Non-integer nonce values cause schema validation failure","Missing required fields result in 400 Bad Request","Payment not included or insufficient USDC results in 402 Payment Required","Network timeout if Base or Solana payment rails are congested"],"whenToPreferThis":"Use this endpoint when an AI agent or wallet automation system needs to perform a zero-knowledge, verifiable preflight check before broadcasting a nonce-replacement EVM transaction. It is ideal when you need cryptographic evidence (SHA256 of inputs) that the check was performed without data retention or external calls — useful in auditable, trust-minimized agent pipelines. Prefer this over on-chain lookups when you need a fast, cheap ($0.001 USDC), off-chain computation with verifiable delivery guarantees via x402.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-01T00:54:01.491Z","isFirstParty":false,"canonicalSlug":"delx-commerce-evm-nonce-replace-check-a0b6ff7b"}