apipay-mcp

Give your AI agent a prepaid balance it can spend on API calls. One top-up, no per-provider signups, no key management: the agent discovers APIs, calls them, and pays per call from the balance — mid-conversation.

Three tools: search_apis, call_api, check_balance. When the balance runs out, the agent receives a machine-readable payment link to hand to you.

1. Get a token (shown once)

curl -X POST https://apipay.fly.dev/v1/signup \
  -H "content-type: application/json" \
  -d '{"email":"[email protected]"}'

New accounts start with 500 trial credits (1 credit = $0.01).

2. Install

Claude Code

claude mcp add apipay -e APIPAY_TOKEN=<your-token> -- npx -y apipay-mcp

Claude Desktop (claude_desktop_config.json)

{
  "mcpServers": {
    "apipay": {
      "command": "npx",
      "args": ["-y", "apipay-mcp"],
      "env": { "APIPAY_TOKEN": "<your-token>" }
    }
  }
}

Cursor (~/.cursor/mcp.json)

{
  "mcpServers": {
    "apipay": {
      "command": "npx",
      "args": ["-y", "apipay-mcp"],
      "env": { "APIPAY_TOKEN": "<your-token>" }
    }
  }
}

3. Use it

Ask your agent things like:

find a web search API and look up today's HN front page

The agent will search_apis, then call_api with the slug it found; the per-call cost and remaining balance come back with every result. Top up any time at the link check_balance returns.

Env vars: APIPAY_TOKEN (required), APIPAY_BASE_URL (optional override, defaults to the hosted gateway).

If your token leaks

Rotate it immediately — the old token stops working the instant the new one is issued; your balance, account id, and vaulted keys are untouched:

curl -X POST https://apipay.fly.dev/v1/token/rotate \
  -H "Authorization: Bearer <your-current-token>"

The response contains your new token (shown once). Update APIPAY_TOKEN in your MCP config afterwards. You can also remove a vaulted provider key at any time with DELETE /v1/keys/<provider-slug> using the same auth header.