Pay-per-Attestation: an AI agent pays to seal its own decision (input hash,…
Pay-per-Attestation: an AI agent pays to seal its own decision (input hash, output, model, timestamp) in FractalAI's post-quantum L1 — Dilithium-3 (NIST FIPS 204) signed, Black-Box chained; on-chain anchoring (VAID-1) is attempted per call and reported in the response. Pay-per-Attestation: an AI agent pays to seal its own decision (input hash, output, model, timestamp) in FractalAI's post-quantum L1 — Dilithium-3 (NIST FIPS 204) signed, Black-Box chained; on-chain anchoring (VAID-1) is attempted per call and reported in the response. Returns a re-verifiable receipt. Built for EU AI Act Art.12 record-keeping. x402-native.
1 route settlement-verified · $0.05 USDC/request · 1 endpoint · Verification · base network · x402 protocol
Verified routes
POST /api/x402/attest-decision· $0.05 · 2026-10-21 · 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
Pay-per-Attestation: an AI agent pays to seal its own decision (input hash,… is listed in the Verification category with pricing at $0.05 USDC/request. One route has been settlement-verified by PayAPI Market on 2026-10-21. 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 1 endpoint.
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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