{"uid":"cap_O-_CrIGNZQl6AGtpX9r2L","slug":"idempotency-replay-guard-01f1945a","name":"Idempotency Replay Guard","description":"Detect safe replays and conflicting reuse of an idempotency key","url":"https://phion.systems/v1/paid/trust/idempotency-replay-guard","method":"POST","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema"},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","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":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_fXko2sAeVy53zJtImoc8m","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Detects whether reuse of an idempotency key is a safe replay of a prior request or a conflicting misuse that should be rejected","exampleAgentPrompt":"Before retrying this payment, check whether idempotency key 'pay-abc-1234' is a safe replay of a prior identical request or a conflicting reuse with different parameters.","exampleUseCases":[{"title":"Safe payment retry verification","prompt":"I'm about to retry a failed payment with idempotency key 'txn-7f3a-9812' — can you check whether this is a safe identical replay or if the key was already used for a different amount or recipient?"},{"title":"Detecting conflicting key reuse in agent loop","prompt":"My agent loop may have submitted the same tool call twice with key 'agent-op-5521' but with slightly different inputs — can you check if that's a safe replay or a conflict I need to resolve?"},{"title":"Audit idempotency violations before reconciliation","prompt":"Before I reconcile today's transactions, flag any idempotency keys that were reused with conflicting payloads rather than safe identical retries — here's the key list from today's run."}],"resultDescription":"Returns a classification of the idempotency key reuse as either a safe replay (identical request repeated) or a conflicting reuse (same key, different parameters), along with relevant flags and evidence to guide the caller's decision on whether to proceed, reject, or escalate.","failureModes":["Insufficient key or payload context provided — returns validation error","Key not found in prior request history — cannot determine replay vs. conflict","Ambiguous payload diff — partial match may yield inconclusive classification","Malformed idempotency key format — rejected at input validation","Service unavailable or timeout — caller should not assume safe replay"],"whenToPreferThis":"Use this endpoint when an agent or system is about to retry an operation and needs to verify whether the idempotency key is being reused safely (identical request) or dangerously (different payload or intent). Especially valuable in x402 payment flows, multi-step agentic pipelines, or any workflow where duplicate execution has financial or state consequences. Prefer this over ad-hoc key comparisons when you need a structured, policy-driven verdict rather than a simple equality check.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T06:44:42.078Z","isFirstParty":false}