Google Tasks MCP Server

This Model Context Protocol (MCP) server provides a bridge between MCP clients and Google Tasks, allowing you to manage your task lists and tasks directly from clients like Claude Desktop, Cursor, and Codex.

[!NOTE] All (bar some edits) code in this project was "vibe coded" - generated with Claude/Copilot with instructions from me.

Features

This MCP server provides the following functionality:

Task List Management

• list-tasklists - List all your task lists
• get-tasklist - Get details about a specific task list
• create-tasklist - Create a new task list
• update-tasklist - Update an existing task list
• delete-tasklist - Delete a task list

Task Management

• list-tasks - List all tasks in a task list, including paginated results
• get-task - Get details about a specific task
• create-task - Create a new task
• update-task - Update an existing task
• delete-task - Delete a task
• complete-task - Mark a task as completed
• move-task - Move a task (reorder, change parent, or move across task lists)
• clear-completed-tasks - Clear all completed tasks from a list

Authentication Flow

When you first use the Google Tasks MCP server:

1. Use the authenticate tool to get an authorization URL
2. Visit the URL in your browser and sign in with your Google account
3. After authorizing, you'll receive a code on the browser page
4. Use the set-auth-code tool with this code to complete authentication
5. You can now use all other tools to interact with Google Tasks

Note: Your authentication tokens (including refresh tokens) are automatically saved to disk at ~/.config/google-tasks-mcp/credentials.json with restricted permissions (600). This means:

• You only need to authenticate once - credentials persist across server restarts
• Automatic token refresh - Access tokens are automatically refreshed when they expire (typically after 1 hour) using the saved refresh token
• No re-authentication needed - After the initial setup, you won't need to authenticate again unless you revoke access or delete the credentials file

Implementation Features

This MCP server includes the following improvements:

• Persistent token storage - Authentication credentials are saved to disk (~/.config/google-tasks-mcp/credentials.json) with restricted permissions, so you only need to authenticate once
• Environment variable validation - Startup validation ensures required credentials are configured with clear error messages
• Automatic token refresh - OAuth tokens are automatically refreshed when they expire, eliminating the need to re-authenticate during active sessions or after restarts
• Enhanced input validation - Comprehensive validation of all inputs including ID formats, string lengths, and RFC 3339 date formats
• HTML sanitization - OAuth callback responses are sanitized to prevent XSS vulnerabilities
• Graceful shutdown - Proper cleanup of resources on SIGINT/SIGTERM signals
• Type safety - Full TypeScript type safety throughout the codebase with proper interfaces
• Configurable redirect URI - The OAuth redirect URI can be customized via the GOOGLE_REDIRECT_URI environment variable

Screenshots

Claude Desktop

Cursor

Setup Instructions

1. Create Google Cloud Project & Enable API

1. Go to the Google Cloud Console
2. Create a new project
3. Navigate to "APIs & Services" > "Library"
4. Search for "Google Tasks API" and enable it
5. Go to "APIs & Services" > "Credentials"
6. Click "Create Credentials" > "OAuth Client ID"
7. Configure the OAuth consent screen (External is fine for personal use)
8. For Application Type, select "Web application"
9. Add "http://localhost:3000/oauth2callback" as an authorized redirect URI
10. Create the client ID and secret

2. Configure Environment Variables

Create a .env file in this project directory:

GOOGLE_CLIENT_ID=your_client_id_here
GOOGLE_CLIENT_SECRET=your_client_secret_here
GOOGLE_REDIRECT_URI=http://localhost:3000/oauth2callback

Environment Variables:

• GOOGLE_CLIENT_ID (required) - Your Google OAuth Client ID
• GOOGLE_CLIENT_SECRET (required) - Your Google OAuth Client Secret
• GOOGLE_REDIRECT_URI (optional) - OAuth redirect URI (defaults to http://localhost:3000/oauth2callback)

Note: The server validates that GOOGLE_CLIENT_ID and GOOGLE_CLIENT_SECRET are set at startup and will fail with clear error messages if they are missing or invalid.

3. Build the Server

1. Install dependencies:

npm install

2. Build the server:

npm run build

4. Configure an MCP Client

Codex

Add the server to ~/.codex/config.toml:

[mcp_servers.google-tasks]
command = "zsh"
args = ["-lc", "cd /path/to/google-tasks-mcp && exec node build/index.js"]

Replace /path/to/google-tasks-mcp with the path to this project, then restart Codex.

To verify the server is registered:

codex mcp list
codex mcp get google-tasks

Claude for Desktop

1. Install Claude for Desktop
2. Open the Claude configuration file:
   • MacOS: ~/Library/Application Support/Claude/claude_desktop_config.json
   • Windows: %APPDATA%\Claude\claude_desktop_config.json
3. Add the Google Tasks MCP server configuration:

{
  "mcpServers": {
    "google-tasks": {
      "command": "node",
      "args": ["/path/to/google-tasks-mcp/build/index.js"]
    }
  }
}

Replace the path with your own value, then restart Claude for Desktop.

Requirements

• Node.js 20+ (see package.json engines)
• An MCP-compatible client
• Google Cloud Project with Tasks API enabled

License

This project is for demonstration purposes only. Use at your own risk.