macOS Calendar MCP Server

A Model Context Protocol (MCP) server for seamless macOS Calendar integration using AppleScript. No OAuth setup required!

Features

• 🍎 Native macOS Integration - Uses AppleScript to interact directly with macOS Calendar
• 📅 Full Calendar Management - Create, list, and search calendar events
• 🚀 Zero Configuration - No OAuth, no API keys, just works out of the box
• 🔧 MCP Compatible - Works with Claude Code CLI and other MCP clients
• 📱 Multi-Calendar Support - Works with all your calendars (Personal, Work, etc.)

Quick Start

Prerequisites

• macOS (required for AppleScript support)
• Node.js 16+
• Calendar app (pre-installed on macOS)

Installation

1. Clone the repository:

git clone https://github.com/xybstone/macos-calendar-mcp.git
cd macos-calendar-mcp

2. Install dependencies:

npm install

3. Grant permissions:
   • When first run, macOS will ask for Calendar app permissions
   • Grant access to allow the MCP server to manage your calendars

Usage with Claude Code CLI

Add to your .claude_project file:

{
  "mcpServers": {
    "macos-calendar": {
      "command": "node",
      "args": ["/path/to/macos-calendar-mcp/macos-calendar-mcp.js"]
    }
  }
}

Or run directly:

node macos-calendar-mcp.js

Available Tools

| Tool | Description | Parameters | |------|-------------|------------| | list-calendars | List all available calendars | None | | create-event | Create a new calendar event | title, startDate, endDate, calendar, description, location | | list-today-events | List today's events | calendar (optional) | | search-events | Search events by keyword | query, calendar (optional) |

Examples

Create an Event

{
  "title": "Team Meeting",
  "startDate": "2025-07-05 14:00",
  "endDate": "2025-07-05 15:00", 
  "calendar": "Work",
  "description": "Weekly team sync",
  "location": "Conference Room A"
}

List Calendars

// Returns all available calendars

Search Events

{
  "query": "meeting",
  "calendar": "Work"
}

Date Format

Use the format: YYYY-MM-DD HH:MM (24-hour format)

Examples:

• 2025-07-05 14:00 (2:00 PM)
• 2025-12-25 09:30 (9:30 AM)
• 2025-07-10 18:00 (6:00 PM)

Time Zone Handling:

• Uses native macOS time handling to avoid timezone conversion issues
• All times are interpreted in your system's local timezone
• No UTC conversion or daylight saving adjustments needed

Supported Calendars

Works with all macOS Calendar calendars including:

• Personal calendars
• Work calendars
• Shared calendars
• Subscribed calendars (iCloud, Google, etc.)

Troubleshooting

Permission Issues

If you get permission errors:

1. Open System Preferences → Security & Privacy → Privacy
2. Select "Calendar" from the left sidebar
3. Ensure Terminal (or your app) has access

AppleScript Errors

• Ensure Calendar app is installed and accessible
• Check calendar names are correct (case-sensitive)
• Verify date formats match the expected pattern

Time Zone Issues

If events appear at wrong times:

1. Check your system timezone settings
2. Use the fix-event-times tool to correct existing events
3. Ensure date format is YYYY-MM-DD HH:MM in 24-hour format
4. The MCP uses native macOS time handling to avoid conversion issues

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Test thoroughly on macOS
5. Submit a pull request

License

MIT License - see LICENSE file for details.

Why This MCP?

Unlike Google Calendar integrations that require complex OAuth setups, this MCP:

• ✅ Works immediately with no configuration
• ✅ Integrates with your existing macOS Calendar setup
• ✅ Supports all calendar sources (iCloud, Google, Exchange, etc.)
• ✅ Requires no internet connection for basic operations
• ✅ Respects your privacy - everything runs locally

Perfect for developers who want calendar integration without the OAuth headache!

Privacy & Security

• ✅ Local Processing: All calendar operations run locally on your machine
• ✅ No Data Upload: Your calendar data never leaves your device
• ✅ Privacy Focused: No OAuth tokens, no cloud services, no tracking
• ⚠️ Private Data: When testing, avoid committing files containing personal events to public repositories

Data Protection

The project includes .gitignore patterns to prevent accidental commits of private event data:

• *events*.json - Event data files
• *meetings*.json - Meeting schedules
• *schedule*.json - Schedule files
• private-*.json - Any private data files