{"uid":"cap_Q7o9Tpba8gHRVufdwDEpy","slug":"witness-fact-notarization-61e72ed1","name":"Witness Fact Notarization","description":"Paid, attributable, perishable observation of public web facts. Run POST /quote first (free): a 200 means the experiment can be performed; only then pay POST /witness ($0.01 USDC via x402, Base or Solana) for a signed receipt. Receipts bind their full method, expire in 1h, and are rendered with contradictions and expiry visible at GET /observatory. Agent docs: /llms.txt and /skill.md. Signing key: GET /pubkey. Payment descriptor: GET /.well-known/x402. robots.txt disallows /witness for crawlers.","url":"https://witness.outbid.sh/witness","method":"POST","headers":{},"bodySchema":null,"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","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":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_X0dGzozz8zLMnVRERs6WH","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Creates an independently signed receipt attesting to a fact or statement, providing cryptographic proof of witnessing at a point in time.","exampleAgentPrompt":"Can you get an independent signed receipt attesting to this fact: 'Company XYZ agreed to deliver 500 units by June 30, 2025'? I need a cryptographic witness record I can reference later.","exampleUseCases":[{"title":"Legal agreement timestamp proof","prompt":"I need to record and independently witness the fact that our contract terms were agreed upon today — can you get a signed receipt attesting to: 'Client Acme Corp accepted terms v2.3 on 2025-06-15'?"},{"title":"AI agent output provenance","prompt":"Can you get a witness receipt for this AI-generated report summary so I can prove what the model said at this exact moment: 'Risk assessment score: 7.2, generated by model v4.1 on 2025-06-15'?"},{"title":"Audit trail for data pipeline","prompt":"I need a cryptographic attestation that this data hash existed at this point in time — please witness the fact: 'Dataset checksum sha256:abc123def456 was validated clean at pipeline step 3 on 2025-06-15'."}],"resultDescription":"A signed receipt containing a cryptographic attestation of the submitted fact or statement, including a timestamp and independent signature that can be used to prove the fact was witnessed at a specific point in time.","failureModes":["Payment not included or insufficient USDC — request rejected with 402","Empty or missing fact/statement body — validation error","Malformed request payload — 400 bad request","Service unavailable — 503 or timeout","Receipt signing failure — internal error on the provider side"],"whenToPreferThis":"Choose this endpoint when you need an independent, cryptographically signed attestation of a fact or statement at a specific moment in time — particularly for audit trails, legal evidence, AI output provenance, or any situation where a trusted third-party witness signature adds value. Prefer this over simple hashing or self-signed records when independent verification and non-repudiation are required.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T12:38:01.150Z","isFirstParty":false}