Chatmux MCP Server

chatmux

Local-first personal chat data layer daemon. Connects IM platforms (v0.1: LINE) via child-process adapters, stores messages to JSONL + SQLite/FTS5, exposes MCP tools for AI clients.

The three repos

chatmux is the core. Platforms plug in below it, consumers sit above it, and both sides of that boundary live in their own repos:

Adapters speak the adapter protocol; consumers speak MCP. Either side can be replaced without touching the other.

Quickstart

1. Install

git clone https://github.com/echoedinvoker/chatmux.git
cd chatmux
bun install

2. First login (QR code)

bun run start
# A QR code will appear in the terminal
# Open LINE on your iPhone → tap QR scanner → scan
# After successful login, authToken is saved for future auto-login

3. Connect Claude Code

Register the daemon's MCP endpoint with Claude Code:

claude mcp add --transport http chatmux http://127.0.0.1:7717/mcp
claude mcp list   # chatmux: ... - ✔ Connected

The daemon listens on two transports at once: a TCP port on 127.0.0.1 (default 7717) for standard MCP clients like Claude Code, and a unix socket for same-host sidecar consumers like chat.nvim. Use the TCP url for Claude Code — the MCP spec only defines stdio and streamable HTTP transports, so no MCP client accepts a unix socket path.

Port is configurable via CHATMUX_MCP_PORT, or mcp.port in adapters.json; set it to 0 to disable the TCP listener. See docs/mcp-interface.md.

Architecture

LINE adapter ←── stdio JSON-RPC ──→ core daemon ←── MCP Streamable HTTP ──→ Claude Code
(Node+tsx)        (child process)    (Bun)         (127.0.0.1 TCP / unix)     (MCP client)
                                     ├─ SafetyRail
                                     ├─ Storage (JSONL → SQLite/FTS5)
                                     ├─ Adapter Runner
                                     └─ MCP Server

• Core daemon (Bun): central process managing storage, safety, and MCP server
• LINE adapter (Node+tsx): child process connecting to LINE via IOSIPAD slot
• Storage: JSONL append-only truth source + SQLite/FTS5 queryable view
• MCP server: Streamable HTTP over loopback TCP (standard MCP clients) + unix socket (same-host sidecars), 6 tools + 4 resources

MCP Tools

MCP Resources

Writing a consumer

Core exposes primitives, not policy. Anything that decides what matters — which chats are worth surfacing, where a notification goes, when to stay quiet — belongs in a consumer, on the far side of the MCP boundary.

examples/notifier/ is a working reference: it tails the event log with a persisted cursor and hands each message to a hook you fill in. Its mcp-client.ts uses raw fetch rather than the TypeScript SDK, so it doubles as a wire-protocol reference for consumers in any language.

systemd Service

cp config/chatmux.service ~/.config/systemd/user/
systemctl --user daemon-reload
systemctl --user enable --now chatmux

Development

bun run dev     # Start with --watch (auto-reload)
bun test        # Run all tests
bun run start   # Start daemon

See docs/ for detailed architecture and protocol documentation.

⚠️ Account Risk Warning

This project uses @evex/linejs, an unofficial LINE client library. Using unofficial APIs may violate LINE's Terms of Service. Your LINE account may be restricted, suspended, or permanently banned. Use at your own risk.

The IOSIPAD device slot is used to avoid interfering with your phone's LINE app, but LINE may change their multi-device policy at any time.

⚠️ Legal Disclaimer

This software is provided "as is", without warranty of any kind. The author is not responsible for any consequences of using this software, including but not limited to account restrictions, data loss, or violations of third-party terms of service.

This is a personal tool for personal use. Do not use it for spam, harassment, unauthorized access to others' messages, or any illegal activity.

🔒 Privacy Disclosure

chatmux stores decrypted message content in plaintext on your local machine:

• ~/.local/share/chatmux/events.jsonl — all events (append-only)
• ~/.local/share/chatmux/chatmux.db — SQLite database with messages, contacts, chats
• ~/.local/share/chatmux/adapters/line/auth.json — LINE auth token
• ~/.local/share/chatmux/adapters/line/storage.json — E2EE key storage

These files are protected by filesystem permissions (owner-only). Do not share these files. The auth token grants full access to your LINE account. The E2EE keys can decrypt your messages.

v0.1 does not encrypt the database. SQLCipher encryption is planned for v0.2.

License

MIT