@zettapay/mcp

Accept crypto from an AI agent in one tool call — non-custodial, self-hosted.

A Model Context Protocol server that lets an AI agent (Claude Desktop, Claude Code, or any MCP client) create and track crypto invoices through your own ZettaPay listener.

It runs on your machine and talks only to your local listener (http://localhost:8787 by default). It never holds a key, never holds funds, and never phones home. Payments settle straight to your wallet on-chain.

What it does

Three tools, mapped 1:1 onto the listener's HTTP API:

| Tool | Does | | --- | --- | | create_invoice | Create a BTC or USDC/USDT-on-Base invoice; returns the receive address + payment/QR URI. | | get_invoice_status | Poll an invoice: pending \| partial \| confirmed \| expired \| failed. | | list_supported_assets | List what the listener accepts: btc, usdc-base, usdt-base. |

Prerequisites

1. A running ZettaPay listener you control:

   npm i -g @zettapay/listener
   zettapay-listener start

2. Node.js >= 18.18.

Configure

The server reads two environment variables:

| Var | Default | Notes | | --- | --- | --- | | LISTENER_URL | http://localhost:8787 | Your local listener's base URL. | | ZETTAPAY_API_KEY | (none) | Sent as X-ZettaPay-Api-Key when your listener requires auth. |

Claude Desktop

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "zettapay": {
      "command": "npx",
      "args": ["-y", "@zettapay/mcp"],
      "env": {
        "LISTENER_URL": "http://localhost:8787",
        "ZETTAPAY_API_KEY": "sk_live_..."
      }
    }
  }
}

Claude Code

claude mcp add zettapay -- npx -y @zettapay/mcp

(Set LISTENER_URL / ZETTAPAY_API_KEY in the environment, or via your client's MCP env config.)

Any MCP client (stdio)

LISTENER_URL=http://localhost:8787 ZETTAPAY_API_KEY=sk_live_... npx -y @zettapay/mcp

The server speaks MCP over stdio. Diagnostic logs go to stderr so they never corrupt the JSON-RPC stream.

Example agent flow

"Create a $42 USDC invoice on Base and give me the address."

The agent calls create_invoice({ chain: "base", amount_usd: 42 }) and gets back the receive address, the exact amount, and an EIP-681 payment URI — then it can poll get_invoice_status({ invoice_id }) until the status flips to confirmed.

Non-custodial by construction

This package is a thin client for your listener. The agent never sees a private key or an xpub; it only ever receives a public receive address. All custody guarantees of the listener hold unchanged — ZettaPay never touches your money. No identity checks, no telemetry, no third party.

License

MIT