FairSeal Cryptographic Receipts API
Cryptographic receipts for AI decisions & game outcomes: notarize agent decisions, anchor SHA-256 hashes on Base, VDF-proven RNG, PII detection. Every call returns a receipt you can verify offline.
1 of 7 routes settlement-verified · $0.001–$0.05 USDC/request · 7 endpoints / 17 tools · Verification · base network · x402 protocol
Verified routes
GET /v1/rng/latest· $0.01 · 2026-10-15 · receipt
Other routes are unverified.
Networks: Base (settlement-verified)
Discovery is free. Agents search the catalogue here. Payment happens on the listing 402, not on PayAPI.
url https://payapi.market/mcpAbout this API
FairSeal Cryptographic Receipts API is listed in the Verification category with pricing at $0.001–$0.05 USDC/request. One route has been settlement-verified by PayAPI Market on 2026-10-15. View receipt on Basescan.
Payments settle on base in USDC via the x402 protocol. AI agents discover this API through the PayAPI Market MCP server and pay per request without API keys or accounts.
This API exposes 7 endpoints. Only the verified route has been tested by PayAPI Market. Other routes are unverified.
How to call this API
Every protected route returns HTTP 402 with x402 payment requirements. An agent pays the stated USDC amount on Base and retries with the payment header. No API keys, no accounts. Browse the marketplace or list your own API.
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By FairSeal