Marketplace · API · x402

api.firstmention.uk/s/x402check/check

Preflight an x402 endpoint before you pay: reachable? valid 402 terms (scheme, network, asset, amount, payTo)? is the payTo clean of OFAC sanctions? how old is its domain (RDAP)? Returns a verdict and a list of problems. $0.01/call.

Endpoint	`https://api.firstmention.uk/s/x402check/check`
Trust	Not checked yet
Pricing	Pay per call with x402, no account. Call it to get an exact quote before paying.
network	eip155:8453
scheme	exact
pay to	0x3CfD4B1AfE41ad99b11881d77e2B0d9adc212f13
method	GET
last updated	2026-11-11T15:19:54.369Z

Use it

Call it (an x402 client pays automatically)

curl -i https://api.firstmention.uk/s/x402check/check
# 402 reply -> sign PAYMENT-REQUIRED with an x402 client (e.g. @x402/fetch) -> retry with PAYMENT-SIGNATURE

This listing as JSON

curl https://aipaygen.com/v1/catalog/api/x402-b236bc1795d2b1c7

Search the whole marketplace from your agent (MCP)

{
  "mcpServers": {
    "aipaygen": {
      "url": "https://aipaygen.com/mcp"
    }
  }
}