Billy MCP Server

Billy (billy.dk) accounting: invoices, journal entries, trial balance, with write protection.

Local serverstdioTypeScript

What is the Billy MCP server?

Connect Billy to Claude, Cursor or any other MCP client and it stops being a tab you switch to. Billy (billy.dk) accounting: invoices, journal entries, trial balance, with write protection. The billy mcp server is what makes that connection.

What the server does

Log into mit.billy.dkSettings → Access tokens → Create access token. Tokens are per-company and don't expire.

Installation

billy-mcp on npm is all you need. Most clients run it directly, so configuration is a few lines and a restart.

Credentials and setup notes

Configuration is passed through the environment: BILLY_ACCESS_TOKEN, BILLY_ORGANIZATION_ID, BILLY_BASE_URL. Treat anything key-shaped as a real credential — scope it to the minimum the server needs, and rotate it if it ever lands in a shared config.

Worth knowing first

  • It runs with your machine's permissions. That is convenient and also the reason to think about what you point it at before you approve a tool call.
  • Missing credentials fail quietly in some clients — if no tools show up, check the environment block first.
  • Keep per-call confirmation enabled while you learn its behaviour; it is the cheapest safeguard you have.

Where it fits

Among the developer tooling options, the useful question is rarely "what can it do" but "what does it cost you to run" — permissions, credentials, and how much of your context its toolset consumes. It is maintained by Thourum; worth a glance at recent repository activity before you build anything load-bearing on it.

SyncDev reviews every entry in this directory against the project's own documentation before publishing, and revisits them as servers change.

How to install the Billy MCP server

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

Configuration as documented by the project. Restart the client after saving.

Configuration

VariableDescriptionRequired
BILLY_ACCESS_TOKENCredential the server authenticates with.Yes
BILLY_ORGANIZATION_IDConfiguration value read at startup.Optional
BILLY_BASE_URLEndpoint or connection string the server talks to.Yes

Frequently asked questions

It connects Billy to MCP-compatible AI assistants such as Claude and Cursor. Instead of copying data back and forth by hand, the assistant works with Billy directly.