SlowBooks Switchboard (sbplive)

SlowBooks Switchboard lets Claude (Claude Desktop, Claude Code, or any other program that speaks the Model Context Protocol) work the books of a SlowBooks Pro company. It is a small program, sbplive, separate from SlowBooks Pro: Claude starts it on your computer and talks to it there, and it talks to SlowBooks Pro through the app's own REST API with an API token you make. It does only what that token's role allows, holds no books, never touches the company file or the database, and sends nothing anywhere but your own SlowBooks Pro. Every change Claude makes is in SlowBooks Pro's audit log as token:<label>.

• Free and open source under the Apache License 2.0.

• Python 3.10 to 3.13, standard library only: nothing else to install.

• Both protocol revisions, 2025-11-25 (by handshake) and 2026-07-28 (per request), on stdio and over Streamable HTTP (docs/PROTOCOL.md).

Install

The signed downloads. Each release carries one program per platform: Windows (signed with Azure Trusted Signing), macOS on Apple silicon (signed with a Developer ID and notarized) and Linux x86-64, each with a SHA256SUMS file to check the download against (sha256sum -c SHA256SUMS.linux, or shasum -a 256 -c SHA256SUMS.macos). Unpack it and put sbplive (sbplive.exe on Windows) where it will stay before you run setup: Claude is told where it is, and if you move it, run setup again.

From source, with Python 3.10 or newer:

pipx install git+https://github.com/VonHoltenCodes/SlowBooks-Switchboard
# or, in a virtual environment of your own:
pip install git+https://github.com/VonHoltenCodes/SlowBooks-Switchboard

Either puts sbplive on your path. From a checkout, python -m sbplive works with nothing installed.

Related MCP server: freeagent-cloudflare-mcp

Set it up

1. In SlowBooks Pro, signed in as an administrator, open Settings, API Tokens and make a token: a label you will recognise (it names every change Claude makes) and the role Claude should have, Read-only, Bookkeeper or Accountant. A bookkeeper token is the usual choice. Copy it: it is shown once.

2. Run sbplive setup. It asks where the books are (Enter for this computer, or the address of the office's SlowBooks Pro server), takes the token at a prompt that does not echo, checks it against SlowBooks Pro, stores it for your user only, and connects Claude Desktop (its claude_desktop_config.json, backed up first) and Claude Code (claude mcp add --scope user), both under the name sbplive.

3. Quit Claude Desktop completely and open it again, and ask "What company are you connected to?"

Without questions: sbplive setup --yes --url http://192.168.1.20:3001 --token-file token.txt (--token-file - reads standard input; the token is never a command-line argument).

• sbplive status says whether SlowBooks Pro answers, which company and version, the token's role, whether Claude Desktop and Claude Code are connected, and where the log is.

• sbplive disconnect takes it out of Claude Desktop and Claude Code; --forget also deletes the stored token. To lock it out for good, revoke the token in SlowBooks Pro under Settings, API Tokens.

The whole guide, with what Claude can do under each role, the tools and what to do when something is wrong: docs/GUIDE.md.

From outside the office: the self-hosted door

sbplive serve-http serves the same tools over MCP's Streamable HTTP transport, on this computer only (http://127.0.0.1:8743/mcp), for Claude on the web and the Claude apps through your own Cloudflare Tunnel: nothing is opened on the office's router, and the API token never leaves the computer. With --public-url https://books.example.com (the tunnel's address) Claude signs in with OAuth, and an administrator of the books signs in once on the door's own sign-in page; SlowBooks Pro checks that sign-in and the door keeps nothing of it.

Add it in Claude as a custom connector at https://books.example.com/mcp. The step-by-step guide, from making the token to the tunnel, the connector and turning it off, is docs/REMOTE.md; the sign-in itself is docs/AUTH.md.

Security

• The token is a SlowBooks Pro API token (sbp_...), made under Settings, API Tokens. It is stored in your own configuration folder, readable by you only (mode 600 on macOS and Linux), and sent only to SlowBooks Pro. No API token can manage users or tokens, restore a backup, or change settings or the company file.

• Loopback by default. The stdio server has no network port at all, and serve-http listens on 127.0.0.1 unless told otherwise.

• Plain http only on your own network. An http:// address for SlowBooks Pro is accepted only when it is a private or link-local address (or a name that points to one), and setup warns that the token travels unencrypted there.

• Public means https. An address on the internet must be https://, with a certificate this computer trusts; there is no way to turn the check off. --public-url must be https:// too.

• The log never holds the token, the connector secret, a sign-in, or what was sent.

Found a security problem? Write to support@slowbookspro.com rather than opening a public issue.

Developing

python -m pytest -q                         # needs only pytest; the contract test skips
pip install -r requirements-dev.txt         # the pinned official MCP client
python -m pytest -q tests/test_contract.py  # the contract test, over stdio and HTTP

Every test runs in a home directory of its own and never reads or writes this computer's real configuration. tests/test_end_to_end.py starts a real SlowBooks Pro from a checkout (SBPLIVE_PRODUCT_DIR) and skips, with the reason, without one. Building the executables: docs/BUILD.md. The named tools, client and configuration began as Keith Bloemendaal's MCP server for SlowBooks Pro.

Support

support@slowbookspro.com. SlowBooks Pro: https://www.slowbookspro.com

Copyright 2026 Trent Von Holten. Licensed under the Apache License, Version 2.0; see LICENSE and NOTICE.