Sends a real request to any URL you provide, attaches an Origin header, and…
Sends a real request to any URL you provide, attaches an Origin header, and reads back all six standard cross-origin permission headers the server returns. Sends a real request to any URL you provide, attaches an Origin header, and reads back all six standard cross-origin permission headers the server returns. Tells you whether cross-origin requests are enabled at all, whether your specific origin is permitted, and shows every permission value exactly as the server sent it. Useful for finding why a browser is blocking a request, confirming a new deployment is configured correctly, or auditing whether a public API allows credentialed calls.
1 route settlement-verified · $0.01 USDC/request · 1 endpoint · Verification · base network · x402 protocol
Verified routes
POST /check· $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
Sends a real request to any URL you provide, attaches an Origin header, and… 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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