{"uid":"cap_QFFbdqwKnQV7DXvXb6L4B","slug":"hermes-notar-bitcoin-anchored-sha-256-timestamping-5474c339","name":"Hermes Notar — Bitcoin-anchored SHA-256 Timestamping","description":"Send a SHA-256 digest of your output. Get an instant Nostr-signed receipt and a Bitcoin-anchored OpenTimestamps proof that anyone can verify without trusting us. Use it as proof of delivery, proof of authorship, or audit trail (e.g. EU AI Act logging).","url":"https://notar.185-190-142-134.sslip.io/x402/stamp?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["hash"],"properties":{"hash":{"type":"string","pattern":"^[0-9a-fA-F]{64}$","description":"SHA-256 digest (hex) of your data"},"nostr":{"enum":["1"],"type":"string","description":"hash is a Nostr event id -> NIP-03 later"}}}}},"output":{"type":"object","properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"proof":{"type":"string"},"status":{"type":"string"},"receipt":{"type":"object"},"ots_file":{"type":"string"}}}}}}},"responseSchema":{"type":"json","example":{"proof":"/proof?hash=...","status":"pending","receipt":{"kind":21040,"pubkey":"7e801bc29b782a62fe60b4b4760a3f411c88a0ca5852f623aacea96b9fd4e77b"},"ots_file":"/proof.ots?hash=..."}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","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":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_iu4aeyvKA2FAdUH-O9G9Z","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Accepts a SHA-256 hash, returns a Nostr-signed receipt and an OpenTimestamps proof anchored to the Bitcoin blockchain as tamper-evident evidence of existence at a point in time.","exampleAgentPrompt":"I need to timestamp and notarize the SHA-256 hash a4b3c2d1e5f6... of my AI report — give me a Bitcoin-anchored OpenTimestamps proof and a Nostr-signed receipt I can use as an audit trail.","exampleUseCases":[{"title":"EU AI Act compliance logging","prompt":"We just generated an AI decision report — please timestamp its SHA-256 hash 9f86d081884c7d659a2feaa0c55ad015a3bf4f1b3e699c69b7c2e5f6a8b1d2e3 on the Bitcoin blockchain and get a Nostr-signed receipt so we have an immutable audit trail for EU AI Act compliance."},{"title":"Proof of authorship before publication","prompt":"I've written a whitepaper and computed its SHA-256 digest 3a7bd3e2360a3d29eea436fcfb7e44c735d117c42d1c1835420b6b9942dd4f27 — can you notarize it on Bitcoin using Hermes Notar so I have cryptographic proof I authored it before I publish?"},{"title":"Proof of delivery for a digital asset","prompt":"I just delivered a software build to the client — its SHA-256 hash is b94f6f125179e95a1c11d13e7c49751c23a6c0f4f9b0c6a1e2d3f4a5b6c7d8e. Timestamp and anchor it on Bitcoin so I can prove exactly when delivery happened if there's ever a dispute."}],"resultDescription":"A JSON object containing: a 'status' field (e.g. 'pending' while Bitcoin confirmation is awaited), a 'receipt' object with a Nostr event (kind 21040, pubkey) providing an instant cryptographic signature, an 'ots_file' URL to download the raw OpenTimestamps proof file, and a 'proof' URL to verify the anchoring — all tied to the submitted hash.","failureModes":["Invalid or malformed hash (not 64 hex characters) returns an error — hash must match ^[0-9a-fA-F]{64}$","Payment not completed via x402 protocol results in HTTP 402 and no receipt","Bitcoin anchoring is initially 'pending' until the next OTS aggregation and block confirmation — final proof may take hours","Nostr relay unavailability could delay receipt issuance","Network timeout on the sslip.io host (IP-based domain, no SLA guarantee)"],"whenToPreferThis":"Choose this endpoint when you need a trustless, publicly verifiable, decentralized proof that a piece of data existed at a specific moment in time — without disclosing the data itself. It is ideal for AI audit trails (EU AI Act), proof of authorship, proof of delivery, or any compliance scenario requiring a tamper-evident timestamp. Prefer it over centralized notarization services when verifiability without trusting the provider is required, and over manual OpenTimestamps tooling when you need an automated, pay-per-call API with a Nostr-signed instant receipt in addition to the Bitcoin anchor.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-31T18:34:19.939Z","isFirstParty":false,"canonicalSlug":"hermes-notar-bitcoin-anchored-sha-256-timestamping-5474c339"}