aptu.dev/v1/echo

Echoes a JSON {message} back; the simplest paid call for verifying your x402 payment flow.

Endpoint	`https://aptu.dev/v1/echo`
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	0x169313d28075a6dDB70E7e5190a1eDdc0d105671
method	POST
last updated	2026-11-11T14:53:49.196Z

Use it

Call it (an x402 client pays automatically)

curl -i https://aptu.dev/v1/echo
# 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/x402-665d708520490ce2

Search the whole marketplace from your agent (MCP)

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