Verify an x402 purchase before an AI agent signs
Verify an x402 purchase before an AI agent signs. Validate the live HTTP 402 challenge, Base network, USDC asset, quoted price, recipient, price ceiling, buyer funding, optional gas reserve, and destination hazards, then receive a machine-readable safe-to-sign, fund, review, or reject decision. No account or API key.
1 route settlement-verified · $0.01 USDC/request · 1 endpoint · Verification · base network · x402 protocol
Verified routes
POST /api/payment-guard· $0.01 · 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
Verify an x402 purchase before an AI agent signs is listed in the Verification category with pricing at $0.01 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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