NimBooks MCP

MCP

Your books, answerable in plain language. The assistant can't spend a single Luna.

What it is

nimbooks-mcp is a small Model Context Protocol server that runs on your own machine. Point an AI assistant at it and your Nimiq books become answerable in ordinary sentences: balances, classified history, day-by-day statements priced at each day's close. It can also draft a payment request and hand you back the link. Six tools, about 1,600 lines, no account to create.

"How much came in last month, and who from?"
"Draft a request for 25 NIM for the September retainer."
"Has anyone paid request a1b2c3d4e5 yet?"

The fence

It never signs, it holds no key material, and no server of ours is involved: it reads the public chain and your local backup file, over two network endpoints in total.

It never signs anything. There is no key handling in the package at all. No private key, seed phrase or passphrase is generated, stored, read, derived or asked for, so there is no code path by which a signature could be produced.
A request is not a payment. create_payment_request returns a link. Only the payer's wallet can move money, and only when its owner approves it there.
It writes nothing. Every tool is a read or a pure function. Nothing is built, broadcast or queued, and nothing is marked paid, on chain or in your app's own books. The backup file you point it at is opened read-only.
No server of ours. This process never calls nimbooks.subimpact.net. Three hosts, all public Nimiq infrastructure: rpc.nimiqwatch.com for the chain, v2.nimiqwatch.com for staking rewards (the same analytics API the app reads), and api.coingecko.com for daily prices. That is the whole network surface.

Setup

Node 20 or newer

From npm

One command, nothing to clone or build:

npx -y nimbooks-mcp --help

From source

Prefer to build it yourself, or to read every line before you run it:

git clone https://github.com/subimpact/nimbooks
cd nimbooks/mcp
npm install
npm run build

Then register it with your assistant. Claude Code:

claude mcp add nimbooks -- npx -y nimbooks-mcp \
  --address "YOUR_NQ_ADDRESS"

Claude Desktop: Settings, then Developer, then Edit Config, and add the server to claude_desktop_config.json:

{
  "mcpServers": {
    "nimbooks": {
      "command": "npx",
      "args": [
        "-y", "nimbooks-mcp",
        "--address", "YOUR_NQ_ADDRESS"
      ]
    }
  }
}

Built from source instead? Swap npx -y nimbooks-mcp for node /absolute/path/to/nimbooks/mcp/dist/index.js in either config.

Restart the client and the six tools appear. --address is the account used when a question does not name one; every tool also takes an address of its own. Add --backup /path/to/nimbooks-backup.json if you want it to see the payment requests your app keeps on the device: that file holds cashlink keys, so keep it as carefully as a wallet. The server discards that part of it at the door.