Marketplace · API · x402

http-header-checker.underscoredone.com/check

Sends a request to a web address you provide and reports back everything the server said in response: the status code, all the response headers, how many times it got redirected, and how long the whole thing took.

Endpoint	`https://http-header-checker.underscoredone.com/check`
Trust	✓ Verified callable · 100% uptime over 1 checks · ~572 ms
Pricing	Pay per call with x402, no account. Call it to get an exact quote before paying.
network	eip155:8453
scheme	exact
pay to	0xE9740820225B3918b4ddd1292C7cA4Ca0e2C2F08
method	POST
last updated	2026-11-03T14:53:58.294Z

Use it

Call it (an x402 client pays automatically)

curl -i https://http-header-checker.underscoredone.com/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-b275536e69ea130d

Search the whole marketplace from your agent (MCP)

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