macOS Notify MCP

macOS Notify MCP

A Model Context Protocol (MCP) server for macOS notifications with tmux integration. This tool allows AI assistants like Claude to send native macOS notifications that can focus specific tmux sessions when clicked.

Features

• 🔔 Native macOS notifications using UserNotifications API
• 🖱️ Clickable notifications that focus tmux sessions
• 🎯 Direct navigation to specific tmux session, window, and pane
• 🔊 Customizable notification sounds
• 🚀 Support for multiple concurrent notifications
• 🤖 MCP server for AI assistant integration
• 🖥️ Terminal emulator detection (VSCode, Cursor, iTerm2, Terminal.app)

Installation

Prerequisites

• macOS (required for notifications)
• Node.js >= 18.0.0
• tmux (optional, for tmux integration)

Install from npm

Build from source

Usage

As MCP Server

First, install the package globally:

Quick Setup with Claude Code

Use the claude mcp add command:

Then restart Claude Code.

Manual Setup for Claude Desktop

Edit ~/Library/Application Support/Claude/claude_desktop_config.json:

Available MCP Tools

• send_notification - Send a macOS notification
  • message (required): Notification message
  • title: Notification title (default: "Claude Code")
  • sound: Notification sound (default: "Glass")
  • session: tmux session name
  • window: tmux window number
  • pane: tmux pane number
  • useCurrent: Use current tmux location
• list_tmux_sessions - List available tmux sessions
• get_current_tmux_info - Get current tmux session information

As CLI Tool

Terminal Detection

The tool automatically detects which terminal emulator you're using and uses this information when you click on notifications to focus the correct application. You can test terminal detection with:

Supported Terminal Detection

The tool detects terminals using various methods:

1. Cursor: Via CURSOR_TRACE_ID environment variable
2. VSCode: Via VSCODE_IPC_HOOK_CLI or VSCODE_REMOTE environment variables
3. alacritty: Via ALACRITTY_WINDOW_ID or ALACRITTY_SOCKET environment variables
4. iTerm2: Via TERM_PROGRAM=iTerm.app
5. Terminal.app: Via TERM_PROGRAM=Apple_Terminal

Terminal Detection in tmux

When running inside tmux, the tool attempts to detect which terminal emulator the active tmux client is using:

1. Active Client Detection: Identifies the most recently active tmux client
2. TTY Process Analysis: Traces processes using the client's TTY
3. Environment Preservation: Checks preserved environment variables
4. Process Tree Fallback: Analyzes the process tree as a last resort

For advanced tmux client tracking, see examples/tmux-client-tracking.sh.

How it Works

1. Notification Delivery: Uses a native macOS app bundle (MacOSNotifyMCP.app) to send UserNotifications API notifications
2. Click Handling: When a notification is clicked, the app activates the detected terminal emulator (VSCode, Cursor, iTerm2, alacritty, or Terminal.app) and switches to the specified tmux session
3. Terminal Support: Automatically detects and activates the correct terminal application
4. Multiple Instances: Each notification runs as a separate process, allowing multiple concurrent notifications

Architecture

The project consists of two main components:

1. MCP Server/CLI (TypeScript/Node.js)
   • Implements the Model Context Protocol
   • Provides a command-line interface
   • Manages tmux session detection and validation
2. MacOSNotifyMCP.app (Swift/macOS)
   • Native macOS application for notifications
   • Handles notification clicks to focus tmux sessions
   • Runs as a background process for each notification

MacOSNotifyMCP.app

The MacOSNotifyMCP.app is bundled with the npm package and is automatically available after installation. No additional setup is required.

Troubleshooting

Notifications not appearing

1. Check System Settings → Notifications → MacOSNotifyMCP
2. Ensure notifications are allowed
3. Run macos-notify-mcp -m "test" to verify

tmux integration not working

1. Ensure tmux is installed and running
2. Check session names with macos-notify-mcp --list-sessions
3. Verify terminal app is supported (Alacritty, iTerm2, WezTerm, or Terminal)

Development

License

MIT

Author

Yuki Yano