{"uid":"cap_al2L3TpZ5qPt2Yhft_pCP","slug":"ysaere-notary-hash-receipt-65d9603b","name":"Ysaere Notary — Hash Receipt","description":"Ysaere Notary — pay ~$0.02 USDC → signed hash_only receipt + verify_url; free GET resolve/proof (integrity, not factual truth).","url":"https://api.ysaere.com/v1/notary/receipts","method":"POST","headers":{},"bodySchema":null,"responseSchema":{"type":"json","example":{"data":{"mode":"hash_only","verified":true,"signature":"…","verify_url":"https://api.ysaere.com/v1/notary/receipts/…","content_hash":"v2:sha512:…"},"usage":{"payment_rail":"x402","x402_tx_hash":"0x…","credits_consumed":0},"provenance":{"kind":"external_attestation","mode":"hash_only","signature":"…","verify_url":"https://api.ysaere.com/v1/notary/receipts/…"}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"registry","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_6OA9uUzezuDYCkyA2cBty","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Notarizes a document or data payload by creating a cryptographically signed hash receipt for ~$0.02 USDC, returning a signature and a public verification URL.","exampleAgentPrompt":"Notarize this contract for me — hash it, sign it, and give me a receipt I can share so anyone can verify its integrity later; I'll pay the $0.02 fee.","exampleUseCases":[{"title":"Proof of existence for a contract","prompt":"I just finalized a vendor agreement and need a tamper-proof receipt proving it existed as of today — can you notarize the document content and give me a verify URL I can share with the other party?"},{"title":"Dataset integrity stamp for audit","prompt":"Before I hand off this dataset to the regulator, notarize its hash so we have a signed receipt showing the data was unchanged at submission time."},{"title":"Timestamping creative work","prompt":"I've written a new design spec and want to prove I authored it today — can you hash and sign it with Ysaere so I get a verifiable receipt I can save?"}],"resultDescription":"Returns a JSON object containing: a signed SHA-512 content hash (v2:sha512:…), a cryptographic signature, a public verify_url where anyone can confirm the receipt, the payment rail used (x402), and the on-chain transaction hash. The receipt proves integrity (that the content was unchanged) but not factual truth of the content itself.","failureModes":["Insufficient USDC balance or payment failure — x402 payment not completed, no receipt created","Malformed or missing content body — 400 error, hash cannot be computed","Network timeout during signing — partial failure, receipt may not be issued","Invalid content encoding — the endpoint may reject non-UTF-8 or oversized payloads","Duplicate notarization of identical content — returns a new receipt each time (not idempotent)"],"whenToPreferThis":"Choose this endpoint when you need a lightweight, low-cost (~$0.02) cryptographic proof-of-existence for any document, file, or data payload. It is ideal when you want an externally verifiable, signed receipt without storing the original content — only its hash is retained. Prefer it over full KYB or entity classification endpoints when your goal is integrity attestation rather than identity verification. Best for audit trails, timestamping creative or legal work, or producing receipts that third parties can independently verify via the returned verify_url.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-13T06:34:17.295Z","isFirstParty":false}