Signed spend receipts for agent x402 payments — who paid which call, verifiab...
Signed spend receipts for agent x402 payments — who paid which call, verifiable by a third party. Treasury desk and possession book for agent spend — export, policy, evidence. POST /v1/chat/completions is the x402 USDC door on Base and Solana. Returns signed receipt + public verify_url. Paying this host is real mainnet USDC.
1 route settlement-verified · $0.002 USDC/request · 1 endpoint · Verification · base network · x402 protocol
Verified routes
POST /v1/chat/completions· $0.002 · 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
Signed spend receipts for agent x402 payments — who paid which call, verifiab... is listed in the Verification category with pricing at $0.002 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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