calendar-mcp

Provider-agnostic CalDAV calendar MCP server for AI assistants. Connect any CalDAV calendar to Claude Desktop, Cursor, VS Code, or any MCP-compatible client.

Features

• 10 calendar tools: list_calendars, get_events, get_event, today, upcoming, search_events, free_busy, create_event, update_event, delete_event
• Provider auto-detection: Automatically configures Google, Apple iCloud, Nextcloud, Fastmail from your CalDAV URL
• Any CalDAV server: Works with Radicale, Baikal, ownCloud, or any standard CalDAV provider
• Read-only mode: Optional safety mode that disables all write operations
• Zero external dependencies: Pure Python stdlib for CalDAV/iCal (only mcp SDK required)
• RFC 5545 compliant: Proper iCalendar parsing with recurrence rules, durations, timezones, attendees

Quick Start

pip install calendar-mcp

Configuration

Set three environment variables:

export CALENDAR_MCP_URL="https://caldav.icloud.com/"
export CALENDAR_MCP_USERNAME="you@icloud.com"
export CALENDAR_MCP_PASSWORD="your-app-password"

All Environment Variables

Provider Auto-Detection

Client Configuration

Claude Desktop

{
  "mcpServers": {
    "calendar": {
      "command": "calendar-mcp",
      "env": {
        "CALENDAR_MCP_URL": "https://caldav.icloud.com/",
        "CALENDAR_MCP_USERNAME": "you@icloud.com",
        "CALENDAR_MCP_PASSWORD": "your-app-password"
      }
    }
  }
}

Claude Code

claude mcp add -e CALENDAR_MCP_URL=https://caldav.icloud.com/ -e CALENDAR_MCP_USERNAME=you@icloud.com -e CALENDAR_MCP_PASSWORD=your-app-password calendar calendar-mcp

Tools

Write tools are disabled when CALENDAR_MCP_READ_ONLY=true.

License

Dual-licensed:

• AGPL-3.0 — free for open-source use (see LICENSE)
• Commercial — for proprietary use (see LICENSE-COMMERCIAL)