{"uid":"cap_ibLFXlgI1c4w9OVGIQeiz","slug":"evm-nonce-gap-check-317188ed","name":"EVM Nonce Gap Check","description":"EVM Nonce Gap Check: EVM Nonce Gap Check calculates the gap between pending and proposed transaction nonces from bounded caller-supplied values without an external provider. Call EVM Nonce Gap Check before signing, submitting, replacing, or accepting an EVM/Base transaction assembled from caller-owned data. Returns normalized transaction evidence, calculated budget or shape findings, and a fail-closed preflight status for EVM Nonce Gap Check as versioned deterministic JSON. Price: $0.001 USDC v…","url":"https://api.delx.ai/api/v1/x402/evm-nonce-gap-check","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"maximum_gap":{"type":"integer","description":"Maximum Gap supplied to EVM Nonce Gap Check; used only for this bounded calculation and processed in memory without retention."},"pending_nonce":{"type":"integer","description":"Pending Nonce supplied to EVM Nonce Gap Check; used only for this bounded calculation and processed in memory without retention."},"proposed_nonce":{"type":"integer","description":"Proposed Nonce supplied to EVM Nonce Gap Check; used only for this bounded calculation and processed in memory without retention."}}},"responseSchema":{"type":"json","example":{"result":{"gap":2,"within_budget":false,"possible_replacement":false},"schema":"delx/util-evm-nonce-gap-check/v1","status":"advisory","evidence":{"retained":false,"input_sha256":"b9889d09b1009c8b22542a020475a3b907ede762b24f2fafec69d286c024edfd","external_calls":0},"operation":"evm_preflight:evm_nonce_gap_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_uxH0ObSFxHWQZcyYy2Sy7","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 the gap between a pending and proposed EVM nonce is within a specified maximum budget and whether a replacement is possible.","exampleAgentPrompt":"Check the EVM nonce gap for me — my pending nonce is 5, I'm proposing nonce 7, and my maximum allowed gap is 1. Is it within budget and is a replacement possible?","exampleUseCases":[{"title":"Preflight check before transaction broadcast","prompt":"Before I broadcast this Ethereum transaction, check if a nonce gap of 2 is acceptable — my pending nonce is 3, proposed nonce is 5, and I want a maximum gap of 1."},{"title":"Detect stuck transaction nonce issues","prompt":"I think my transactions might get stuck — my pending nonce is 10 and I'm about to submit with nonce 14. Can you check if that gap of 4 is within a max budget of 3 and whether a replacement is possible?"},{"title":"Agent-driven batch transaction nonce validation","prompt":"My agent is queuing multiple EVM transactions. Validate the nonce spacing: pending nonce is 8, proposed nonce is 9, maximum gap allowed is 2. Is this safe to proceed?"}],"resultDescription":"Returns the computed nonce gap between pending and proposed nonces, a boolean indicating whether the gap is within the specified maximum budget, and a boolean for whether a nonce replacement is possible. Also includes evidence metadata confirming no data is retained and no external calls were made.","failureModes":["Missing required fields (pending_nonce, proposed_nonce, or maximum_gap) may cause validation errors","Non-integer values for nonce fields will be rejected","Negative nonce values may produce unexpected results","Network errors may return 5xx responses"],"whenToPreferThis":"Use this endpoint when an AI agent or automated system needs to preflight-check EVM transaction nonces before submission to avoid gaps that could cause stuck or dropped transactions. Prefer this over manual calculation when operating in high-frequency or multi-agent transaction environments where nonce management is critical.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T07:14:51.188Z","isFirstParty":false}