{"uid":"cap_d6reekuRX8dj4xK2B_RER","slug":"witnessd-vip-witness-endpoint-b9437ac8","name":"witnessd.vip Witness Endpoint","description":"Independently fetch, hash, timestamp and archive a URL or API response; returns a signed certificate. Merkle-anchored on Base hourly. Neutral third-party evidence for agent commerce disputes.","url":"https://witnessd.vip/api/witness?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"url":{"type":"string","format":"uri","description":"The http(s) URL or API endpoint to witness right now"}}},"responseSchema":{"type":"json","example":{"id":"ws_76cae2b76822b099d37882c4","retrieve_url":"https://witnessd.vip/api/retrieve/ws_76cae2b76822b099d37882c4","certificate_url":"https://witnessd.vip/api/certificate/ws_76cae2b76822b099d37882c4"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","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":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_5iSSE2jNDfbLlFBIaxNbh","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Independently fetches, hashes, timestamps, and Merkle-anchors any URL or API response on Base as a neutral third-party witness record","exampleAgentPrompt":"Can you create an independent timestamped witness record of what https://api.example.com/prices returns right now — I need a neutral third-party proof anchored on Base that I can use as an audit trail?","exampleUseCases":[{"title":"AI agent output audit trail","prompt":"Witness the response from https://myagent.io/api/decision/123 right now and give me a certificate I can show auditors proving exactly what the model returned at this moment."},{"title":"Legal evidence of webpage content","prompt":"I need to prove what's currently published at https://competitor.com/claims — can you have an independent service fetch it, timestamp it, and anchor it on the blockchain so I have tamper-proof evidence?"},{"title":"Regulatory compliance snapshot","prompt":"Before this market data feed changes, fetch and certify https://datavendor.com/api/rates/live right now so we have a neutral third-party record of today's published rates for our compliance files."}],"resultDescription":"Returns a JSON object containing a unique witness ID (e.g. ws_76cae2b76822b099d37882c4), a retrieve_url to access the archived response content, and a certificate_url linking to the Merkle-anchored proof on Base that verifies the fetch was performed at a specific time by a neutral third party.","failureModes":["Target URL is unreachable or returns a non-2xx status — witness may still be created but content reflects the error response","Invalid or malformed URL input — API returns a validation error","Payment of $0.02 USDC not fulfilled via x402 — request rejected before fetch is attempted","Target URL requires authentication or blocks external fetchers — returns partial or access-denied content","Network timeout on the target URL — witness may record a timeout rather than content"],"whenToPreferThis":"Choose this endpoint when you need a neutral, independent, blockchain-anchored proof that a specific URL or API endpoint had particular content at a specific moment in time — especially for audit trails, legal evidence, compliance snapshots, or AI agent output verification. Prefer this over simple screenshots or self-hosted archiving when tamper-proof third-party attestation and Merkle anchoring on Base are required. Best suited for single-URL, point-in-time witnessing rather than ongoing monitoring.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-11T00:36:41.821Z","isFirstParty":false,"canonicalSlug":"witnessd-vip-witness-endpoint-b9437ac8"}