{"uid":"cap_R4ujq8v81mxQaqWOABMRh","slug":"evm-batch-duplicate-nonce-check-8bb4a2cf","name":"EVM Batch Duplicate Nonce Check","description":"EVM Batch Duplicate Nonce Check: EVM Batch Duplicate Nonce Check finds duplicate nonces inside a caller-supplied transaction batch from bounded caller-supplied values without an external provider. Call EVM Batch Duplicate Nonce 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 Batch Duplicate Nonce Check as ver…","url":"https://api.delx.ai/api/v1/x402/evm-batch-duplicate-nonce-check","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"nonces":{"type":"array","items":{"type":"integer"},"maxItems":256,"description":"Nonces supplied to EVM Batch Duplicate Nonce Check; used only for this bounded calculation and processed in memory without retention."}}},"responseSchema":{"type":"json","example":{"result":{"unique":false,"duplicate_nonces":[11]},"schema":"delx/util-evm-batch-duplicate-nonce-check/v1","status":"advisory","evidence":{"retained":false,"input_sha256":"93258878a4b3e2c7cf1c455a9ed9b67ff3017ff1d070d0d1a079a29ac92b1af4","external_calls":0},"operation":"evm_preflight:evm_batch_duplicate_nonce_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_kIW2IVhcI130IflC8_O09","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 an array of EVM transaction nonces for duplicates and returns which nonces appear more than once.","exampleAgentPrompt":"Before I submit my batch of EVM transactions, check these nonces for duplicates: [5, 11, 3, 11, 7, 5] — tell me if any are repeated and which ones.","exampleUseCases":[{"title":"Pre-submission EVM batch preflight","prompt":"I'm about to send a batch of 50 EVM transactions. Can you check these nonces for duplicates before I submit them on-chain: [1, 2, 3, 4, 2, 7, 8, 9, 7]?"},{"title":"Debugging failed batch transaction","prompt":"My batch transaction failed and I suspect a nonce collision. Can you scan this list of nonces and tell me which ones are duplicated: [100, 101, 102, 100, 103, 101]?"},{"title":"Agent-generated nonce deduplication audit","prompt":"My agent just generated a set of nonces for a multicall batch — please verify there are no duplicates in this list before I proceed: [0, 1, 2, 3, 4, 5, 0, 6]."}],"resultDescription":"Returns a JSON object indicating whether all nonces are unique (boolean 'unique' field), and an array 'duplicate_nonces' listing any integer nonces that appear more than once in the input. Also includes operation metadata such as whether input was retained (always false) and an input SHA-256 hash for auditability.","failureModes":["Array exceeds 256-item limit — request rejected","Non-integer values in nonce array cause validation error","Empty array input may return trivially unique result","Malformed JSON body returns 400 error"],"whenToPreferThis":"Use this endpoint when you need a fast, in-memory, privacy-preserving check for duplicate nonces across a batch of EVM transactions before submission. Prefer it over manual deduplication logic in your agent when you need an auditable preflight step with input hashing and a clear advisory status. Ideal for batch transaction pipelines, multicall builders, or any workflow where nonce uniqueness is a safety requirement.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T07:14:50.439Z","isFirstParty":false}