{"uid":"cap_wOrBNfbSMQ20HfsOVebZo","slug":"fairseal-notarize-bbbafaf9","name":"FairSeal Notarize","description":"Anchor an AI agent decision or audit record to Base mainnet. Submit {schema, payload_hash (SHA-256 hex, 64 chars), metadata}; service queues into a Merkle batch and returns a receipt with pending_anchor status immediately. Full Merkle proof and on-chain anchor_tx available via free GET /v1/notarize/:receipt_id after batch anchors (within batch_threshold receipts or 120s).","url":"https://api.fairseal.io/v1/notarize","method":"POST","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method","bodyType","body"],"properties":{"body":{"type":"object","required":["schema","payload_hash","metadata"],"properties":{"schema":{"enum":["agent_decision","audit_evidence","probe_record"],"type":"string"},"metadata":{"type":"object","description":"Schema-specific metadata. agent_decision requires {agent_id, decided_at, input_hash, decision_hash}"},"payload_hash":{"type":"string","pattern":"^[0-9a-f]{64}$","description":"SHA-256 hex of full payload (64 lowercase hex chars)"}}},"type":{"type":"string","const":"http"},"method":{"enum":["POST"],"type":"string"},"bodyType":{"enum":["json","form-data","text"],"type":"string"}},"additionalProperties":false}}},"responseSchema":null,"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_3kRCu5iSkUVc4ko6HGfdg","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":"Submits an agent decision, audit evidence, or probe record for cryptographic notarization, anchoring a SHA-256 payload hash in a Merkle batch on Base mainnet and returning a verifiable receipt.","exampleAgentPrompt":"Notarize this agent decision on FairSeal — the schema is 'agent_decision_v1', the SHA-256 payload hash is 'a3f2c1d4e5b6...', and the metadata includes timestamp and agent ID — I need a Merkle-anchored receipt on Base mainnet.","exampleUseCases":[{"title":"Audit trail for autonomous trading agent","prompt":"Record this trade decision my agent just made on FairSeal — schema is 'trade_decision_v1', payload hash is 'b7e3a2d1...', and metadata includes the agent ID and timestamp — I need a receipt anchored on Base mainnet so we have an immutable audit log."},{"title":"Compliance evidence for AI model probe","prompt":"I need to notarize a model probe result for compliance purposes — use schema 'probe_record_v1', the SHA-256 hash of the probe payload is 'c4d9f2a8...', and include the evaluator ID and run timestamp in the metadata."},{"title":"Certify agent safety decision before deployment","prompt":"Before we deploy this agent update, notarize the safety review decision — schema 'safety_review_v1', payload hash 'e1b4c7f3...', metadata should include reviewer ID and decision outcome — I need the Merkle proof receipt for our records."}],"resultDescription":"A cryptographic receipt containing a receipt ID, Merkle proof, and on-chain anchor reference on Base mainnet. The receipt can be independently verified for free via GET /v1/notarize/:receipt_id, which returns the full Merkle proof and on-chain verification data.","failureModes":["Invalid or missing payload_hash (not a valid SHA-256 hex string) — returns 400 Bad Request","Missing required fields (schema or payload_hash) — returns 422 Unprocessable Entity","Payment not provided or insufficient (requires $0.02 USDC via x402) — returns 402 Payment Required","Base mainnet congestion causing delayed anchoring — receipt issued but on-chain confirmation may lag","Duplicate payload hash submission — may create a new receipt for the same hash (not deduplicated)"],"whenToPreferThis":"Choose FairSeal Notarize when you need a lightweight, low-cost ($0.02 USDC) cryptographic receipt anchored on Base mainnet for agent decisions, audit evidence, or probe records. Prefer this over general-purpose blockchain write operations when you want Merkle batch efficiency and a ready-made receipt lookup and proof API without managing your own smart contract or wallet infrastructure. Ideal for AI agent audit trails, compliance evidence, and tamper-proof decision logging in agentic workflows.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T18:36:33.235Z","isFirstParty":false}