Claude Desktop setup

MCP endpoint: https://freetier-agent-api.pages.dev/mcp (Streamable HTTP) · other recipes: Claude Code · Cursor · Generic x402 client (Node / Python)

Claude Desktop runs local MCP servers from claude_desktop_config.json (Settings → Developer → Edit Config). This uses the mcp-remote bridge (needs Node.js) to reach the remote server.

1. Without a key (free calls only)

{
  "mcpServers": {
    "freetier": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://freetier-agent-api.pages.dev/mcp"
      ]
    }
  }
}

2. With a card license key

{
  "mcpServers": {
    "freetier": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://freetier-agent-api.pages.dev/mcp",
        "--header",
        "X-License-Key:${LICENSE_KEY}"
      ],
      "env": {
        "LICENSE_KEY": "YOUR-LICENSE-KEY"
      }
    }
  }
}

No space after the colon in X-License-Key:${LICENSE_KEY} (avoids an argument-quoting bug on Windows). Restart Claude Desktop after saving. On plans with custom connectors you can also add https://freetier-agent-api.pages.dev/mcp under Settings → Connectors (free calls only, since connectors cannot send the header).

How paying works

• Free: every paid tool allows 1 free call per caller, so you can try it before paying.
• Card (no wallet): buy prepaid credits on Gumroad (1,000 credits $3) and send the license key as the X-License-Key header. Failed calls are not charged.
• x402 (USDC on Base): an unpaid call returns the x402 payment requirements; an x402 client signs a USDC payment and retries. Over MCP the payment goes in params._meta["x402/payment"]; over HTTP in the PAYMENT-SIGNATURE header. Desktop chat apps do not sign x402 payments themselves, so use the license key there, or the x402 client recipe for a wallet.

3 prompts to try

1. Check the DNS, SPF and DMARC records for github.com and tell me whether its mail setup has any warnings.

2. When does the domain example.com expire, who is the registrar, and when does its current TLS certificate run out?

3. Geocode "Rådhuspladsen 1, København" and then reverse-geocode the coordinates you get back.

Tools used: dns, domain_whois, ssl_cert, geocode, token_info, invoice_json. Prices: price list.

Agent Extraction API by FreeTier Kits · Terms · llms.txt · /.well-known/x402 · MCP: https://freetier-agent-api.pages.dev/mcp · Contact: tec@mail.grokbot.com
This site and its texts were written with AI assistance and reviewed for accuracy; example outputs are real responses from the API.