Google Workspace MCP Server

Full natural language control over Google Calendar, Drive, Gmail, Docs, Sheets, Slides, Forms, Tasks, and Chat through all MCP clients, AI assistants and developer tools.

The most feature-complete Google Workspace MCP server, now with Remote OAuth2.1 multi-user support and 1-click Claude installation.

Support for all free Google accounts (Gmail, Docs, Drive etc) & Google Workspace plans (Starter, Standard, Plus, Enterprise, Non Profit) with expanded app options like Chat & Spaces. Interested in a private cloud instance? That can be arranged.

See it in action:

A quick plug for AI-Enhanced Docs

This README was written with AI assistance, and here's why that matters

As a solo dev building open source tools, comprehensive documentation often wouldn't happen without AI help. Using agentic dev tools like Roo & Claude Code that understand the entire codebase, AI doesn't just regurgitate generic content - it extracts real implementation details and creates accurate, specific documentation.

In this case, Sonnet 4 took a pass & a human (me) verified them 8/16/25.

Overview

A production-ready MCP server that integrates all major Google Workspace services with AI assistants. It supports both single-user operation and multi-user authentication via OAuth 2.1, making it a powerful backend for custom applications. Built with FastMCP for optimal performance, featuring advanced authentication handling, service caching, and streamlined development patterns.

Simplified Setup: Now uses Google Desktop OAuth clients - no redirect URIs or port configuration needed!

Features

• •

• Complete Gmail management, end to end coverage

• Full calendar management with advanced features

• File operations with Office format support

• Document creation, editing & comments

• Deep, exhaustive support for fine grained editing

• • •

• Form creation, publish settings & response management

• Space management & messaging capabilities

• Spreadsheet operations with flexible cell management

• Presentation creation, updates & content manipulation

• Advanced OAuth 2.0 & OAuth 2.1 support

• Automatic token refresh & session management

• Transport-aware callback handling

• Multi-user bearer token authentication

• Innovative CORS proxy architecture

• •

• Full support for all MCP Transports

• OpenAPI compatibility via mcpo

• Task & task list management with hierarchy

• Programmable Search Engine (PSE) integration

▶ Quick Start

⊠ Credentials

export GOOGLE_OAUTH_CLIENT_ID="..."
export GOOGLE_OAUTH_CLIENT_SECRET="..."

Full setup →

▶ Launch Commands

uvx workspace-mcp --tool-tier core
uv run main.py --tools gmail drive

More options →

★ Tool Tiers

• ● core - Essential tools

• ◐ extended - Core + extras

• ○ complete - Everything Details →

1. One-Click Claude Desktop Install (Recommended)

1. Download: Grab the latest google_workspace_mcp.dxt from the “Releases” page

2. Install: Double-click the file – Claude Desktop opens and prompts you to Install

3. Configure: In Claude Desktop → Settings → Extensions → Google Workspace MCP, paste your Google OAuth credentials

4. Use it: Start a new Claude chat and call any Google Workspace tool

Why DXT?

Desktop Extensions (.dxt) bundle the server, dependencies, and manifest so users go from download → working MCP in one click – no terminal, no JSON editing, no version conflicts.

Required Configuration

Required

Optional

Claude Desktop stores these securely in the OS keychain; set them once in the extension pane.

Prerequisites

• Python 3.10+

• uvx (for instant installation) or uv (for development)

• Google Cloud Project with OAuth 2.0 credentials

Configuration

1. Create Project

console.cloud.google.com

→ Create new project
→ Note project name

Open Console →

2. OAuth Credentials

APIs & Services → Credentials
→ Create Credentials
→ OAuth Client ID
→ Desktop Application

Download & save credentials

3. Enable APIs

APIs & Services → Library

Search & enable:
Calendar, Drive, Gmail,
Docs, Sheets, Slides,
Forms, Tasks, Chat, Search

See quick links below

Complete Setup Process:

1. Create OAuth 2.0 Credentials - Visit Google Cloud Console

   • Create a new project (or use existing)

   • Navigate to APIs & Services → Credentials

   • Click Create Credentials → OAuth Client ID

   • Choose Desktop Application as the application type (no redirect URIs needed!)

   • Download credentials and note the Client ID and Client Secret

2. Enable Required APIs - In APIs & Services → Library

   • Search for and enable each required API

   • Or use the quick links below for one-click enabling

3. Configure Environment - Set your credentials:

   export GOOGLE_OAUTH_CLIENT_ID="your-client-id"
   export GOOGLE_OAUTH_CLIENT_SECRET="your-secret"

≡ Full Documentation →

• Enable Google Calendar API

• Enable Google Drive API

• Enable Gmail API

• Enable Google Docs API

• Enable Google Sheets API

• Enable Google Slides API

• Enable Google Forms API

• Enable Google Tasks API

• Enable Google Chat API

• Enable Google Custom Search API

1.1. Credentials: See Credential Configuration for detailed setup options

2. Environment Configuration:

◆ Development Mode

export OAUTHLIB_INSECURE_TRANSPORT=1

Allows HTTP redirect URIs

@ Default User

export USER_GOOGLE_EMAIL=\
  your.email@gmail.com

Single-user authentication

◆ Custom Search

export GOOGLE_PSE_API_KEY=xxx
export GOOGLE_PSE_ENGINE_ID=yyy

Optional: Search API setup

3. Server Configuration:

◆ Base Configuration

export WORKSPACE_MCP_BASE_URI=
  http://localhost
export WORKSPACE_MCP_PORT=8000

Server URL & port settings

↻ Proxy Support

export MCP_ENABLE_OAUTH21=
  true

Leverage multi-user OAuth2.1 clients

@ Default Email

export USER_GOOGLE_EMAIL=\
  your.email@gmail.com

Skip email in auth flows in single user mode

Google Custom Search Setup

1. Create Search Engine

programmablesearchengine.google.com
/controlpanel/create

→ Configure sites or entire web
→ Note your Engine ID (cx)

Open Control Panel →

2. Get API Key

developers.google.com
/custom-search/v1/overview

→ Create/select project
→ Enable Custom Search API
→ Create credentials (API Key)

Get API Key →

3. Set Variables

export GOOGLE_PSE_API_KEY=\
  "your-api-key"
export GOOGLE_PSE_ENGINE_ID=\
  "your-engine-id"

Configure in environment

Complete Setup Process:

1. Create Search Engine - Visit the Control Panel

   • Choose "Search the entire web" or specify sites

   • Copy the Search Engine ID (looks like: 017643444788157684527:6ivsjbpxpqw)

2. Enable API & Get Key - Visit Google Developers Console

   • Enable "Custom Search API" in your project

   • Create credentials → API Key

   • Restrict key to Custom Search API (recommended)

3. Configure Environment - Add to your shell or .env:

   export GOOGLE_PSE_API_KEY="AIzaSy..."
   export GOOGLE_PSE_ENGINE_ID="01764344478..."

≡ Full Documentation →

Start the Server

▶ Quick Start

uv run main.py

Default stdio mode

◆ HTTP Mode

uv run main.py \
  --transport streamable-http

Web interfaces & debugging

@ Single User

uv run main.py \
  --single-user

Simplified authentication

▶ Selective Tool Loading

# Load specific services only
uv run main.py --tools gmail drive calendar
uv run main.py --tools sheets docs

# Combine with other flags
uv run main.py --single-user --tools gmail

★ Tool Tiers

uv run main.py --tool-tier core      # ● Essential tools only
uv run main.py --tool-tier extended  # ◐ Core + additional
uv run main.py --tool-tier complete  # ○ All available tools

◆ Docker Deployment

docker build -t workspace-mcp .
docker run -p 8000:8000 -v $(pwd):/app \
  workspace-mcp --transport streamable-http

# With tool selection via environment variables
docker run -e TOOL_TIER=core workspace-mcp
docker run -e TOOLS="gmail drive calendar" workspace-mcp

Available Services: gmail • drive • calendar • docs • sheets • forms • tasks • chat • search

Tool Tiers

The server organizes tools into three progressive tiers for simplified deployment. Choose a tier that matches your usage needs and API quota requirements.

Available Tiers

(--tool-tier core) Essential tools for everyday tasks. Perfect for light usage with minimal API quotas. Includes search, read, create, and basic modify operations across all services.

(--tool-tier extended) Core functionality plus management tools. Adds labels, folders, batch operations, and advanced search. Ideal for regular usage with moderate API needs.

(--tool-tier complete) Full API access including comments, headers/footers, publishing settings, and administrative functions. For power users needing maximum functionality.

Important Notes

▶ Start with and upgrade as needed ▶ Tiers are cumulative – each includes all previous ▶ Mix and match with --tools for specific services ▶ Configuration in core/tool_tiers.yaml ▶ Authentication included in all tiers

Usage Examples

# Basic tier selection
uv run main.py --tool-tier core                            # Start with essential tools only
uv run main.py --tool-tier extended                        # Expand to include management features
uv run main.py --tool-tier complete                        # Enable all available functionality

# Selective service loading with tiers
uv run main.py --tools gmail drive --tool-tier core        # Core tools for specific services
uv run main.py --tools gmail --tool-tier extended          # Extended Gmail functionality only
uv run main.py --tools docs sheets --tool-tier complete    # Full access to Docs and Sheets

📋 Credential Configuration

🚀 Environment Variables

export GOOGLE_OAUTH_CLIENT_ID=\
  "your-client-id"
export GOOGLE_OAUTH_CLIENT_SECRET=\
  "your-secret"

Best for production

📁 File-based

# Download & place in project root
client_secret.json

# Or specify custom path
export GOOGLE_CLIENT_SECRET_PATH=\
  /path/to/secret.json

Traditional method

⚡ .env File

cp .env.oauth21 .env
# Edit .env with credentials

Best for development

Loading Priority

1. Environment variables (export VAR=value)

2. .env file in project root (warning - if you run via uvx rather than uv run from the repo directory, you are spawning a standalone process not associated with your clone of the repo and it will not find your .env file without specifying it directly)

3. client_secret.json via GOOGLE_CLIENT_SECRET_PATH

4. Default client_secret.json in project root

Why Environment Variables?

• ✅ Docker/K8s ready - Native container support

• ✅ Cloud platforms - Heroku, Railway, Vercel

• ✅ CI/CD pipelines - GitHub Actions, Jenkins

• ✅ No secrets in git - Keep credentials secure

• ✅ Easy rotation - Update without code changes

🧰 Available Tools

Note: All tools support automatic authentication via @require_google_service() decorators with 30-minute service caching.

📅 Google Calendar calendar_tools.py

📁 Google Drive drive_tools.py

📧 Gmail gmail_tools.py

📝 Google Docs docs_tools.py

📊 Google Sheets sheets_tools.py

🖼️ Google Slides slides_tools.py

📝 Google Forms forms_tools.py

✓ Google Tasks tasks_tools.py

💬 Google Chat chat_tools.py

🔍 Google Custom Search search_tools.py

Tool Tier Legend:

• • Core: Essential tools for basic functionality • Minimal API usage • Getting started

• • Extended: Core tools + additional features • Regular usage • Expanded capabilities

• • Complete: All available tools including advanced features • Power users • Full API access

Connect to Claude Desktop

The server supports two transport modes:

Stdio Mode (Default - Recommended for Claude Desktop)

In general, you should use the one-click DXT installer package for Claude Desktop. If you are unable to for some reason, you can configure it manually via claude_desktop_config.json

Manual Claude Configuration (Alternative)

1. Open Claude Desktop Settings → Developer → Edit Config

   • macOS: ~/Library/Application Support/Claude/claude_desktop_config.json

   • Windows: %APPDATA%\Claude\claude_desktop_config.json

2. Add the server configuration:

{
  "mcpServers": {
    "google_workspace": {
      "command": "uvx",
      "args": ["workspace-mcp"],
      "env": {
        "GOOGLE_OAUTH_CLIENT_ID": "your-client-id",
        "GOOGLE_OAUTH_CLIENT_SECRET": "your-secret",
        "OAUTHLIB_INSECURE_TRANSPORT": "1"
      }
    }
  }
}

2. Advanced / Cross-Platform Installation

If you’re developing, deploying to servers, or using another MCP-capable client, keep reading.

Instant CLI (uvx)

# Requires Python 3.10+ and uvx
# First, set credentials (see Credential Configuration above)
uvx workspace-mcp --tool-tier core  # or --tools gmail drive calendar

Note: Configure OAuth credentials before running. Supports environment variables, .env file, or client_secret.json.

OAuth 2.1 Support (Multi-User Bearer Token Authentication)

The server includes OAuth 2.1 support for bearer token authentication, enabling multi-user session management. OAuth 2.1 automatically reuses your existing - no additional configuration needed!

When to use OAuth 2.1:

• Multiple users accessing the same MCP server instance

• Need for bearer token authentication instead of passing user emails

• Building web applications or APIs on top of the MCP server

• Production environments requiring secure session management

• Browser-based clients requiring CORS support

Enabling OAuth 2.1: To enable OAuth 2.1, set the MCP_ENABLE_OAUTH21 environment variable to true.

# OAuth 2.1 requires HTTP transport mode
export MCP_ENABLE_OAUTH21=true
uv run main.py --transport streamable-http

If MCP_ENABLE_OAUTH21 is not set to true, the server will use legacy authentication, which is suitable for clients that do not support OAuth 2.1.

This implementation solves two critical challenges when using Google OAuth in browser environments:

1. Dynamic Client Registration: Google doesn't support OAuth 2.1 dynamic client registration. Our server provides a clever proxy that accepts any client registration request and returns the pre-configured Google OAuth credentials, allowing standards-compliant clients to work seamlessly.

2. CORS Issues: Google's OAuth endpoints don't include CORS headers, blocking browser-based clients. We implement intelligent proxy endpoints that:

• Proxy authorization server discovery requests through /auth/discovery/authorization-server/{server}

• Proxy token exchange requests through /oauth2/token

• Add proper CORS headers to all responses

• Maintain security by only proxying to known Google OAuth endpoints

This architecture enables any OAuth 2.1 compliant client to authenticate users through Google, even from browser environments, without requiring changes to the client implementation.

Stateless Mode (Container-Friendly)

The server supports a stateless mode designed for containerized environments where file system writes should be avoided:

Enabling Stateless Mode:

# Stateless mode requires OAuth 2.1 to be enabled
export MCP_ENABLE_OAUTH21=true
export WORKSPACE_MCP_STATELESS_MODE=true
uv run main.py --transport streamable-http

Key Features:

• No file system writes: Credentials are never written to disk

• No debug logs: File-based logging is completely disabled

• Memory-only sessions: All tokens stored in memory via OAuth 2.1 session store

• Container-ready: Perfect for Docker, Kubernetes, and serverless deployments

• Token per request: Each request must include a valid Bearer token

Requirements:

• Must be used with MCP_ENABLE_OAUTH21=true

• Incompatible with single-user mode

• Clients must handle OAuth flow and send valid tokens with each request

This mode is ideal for:

• Cloud deployments where persistent storage is unavailable

• Multi-tenant environments requiring strict isolation

• Containerized applications with read-only filesystems

• Serverless functions and ephemeral compute environments

MCP Inspector: No additional configuration needed with desktop OAuth client.

Claude Code Inspector: No additional configuration needed with desktop OAuth client.

VS Code MCP Client Support

{
    "servers": {
        "google-workspace": {
            "url": "http://localhost:8000/mcp/",
            "type": "http"
        }
    }
}

Reverse Proxy Setup

If you're running the MCP server behind a reverse proxy (nginx, Apache, Cloudflare, etc.), you have two configuration options:

Problem: When behind a reverse proxy, the server constructs OAuth URLs using internal ports (e.g., http://localhost:8000) but external clients need the public URL (e.g., https://your-domain.com).

Solution 1: Set WORKSPACE_EXTERNAL_URL for all OAuth endpoints:

# This configures all OAuth endpoints to use your external URL
export WORKSPACE_EXTERNAL_URL="https://your-domain.com"

Solution 2: Set GOOGLE_OAUTH_REDIRECT_URI for just the callback:

# This only overrides the OAuth callback URL
export GOOGLE_OAUTH_REDIRECT_URI="https://your-domain.com/oauth2callback"

You also have options for: | OAUTH_CUSTOM_REDIRECT_URIS (optional) | Comma-separated list of additional redirect URIs | | OAUTH_ALLOWED_ORIGINS (optional) | Comma-separated list of additional CORS origins |

Important:

• Use WORKSPACE_EXTERNAL_URL when all OAuth endpoints should use the external URL (recommended for reverse proxy setups)

• Use GOOGLE_OAUTH_REDIRECT_URI when you only need to override the callback URL

• The redirect URI must exactly match what's configured in your Google Cloud Console

• Your reverse proxy must forward OAuth-related requests (/oauth2callback, /oauth2/*, /.well-known/*) to the MCP server

# Configure credentials first (see Credential Configuration section)

# Start with specific tools only
uvx workspace-mcp --tools gmail drive calendar tasks

# Start with tool tiers (recommended for most users)
uvx workspace-mcp --tool-tier core      # Essential tools
uvx workspace-mcp --tool-tier extended  # Core + additional features
uvx workspace-mcp --tool-tier complete  # All tools

# Start in HTTP mode for debugging
uvx workspace-mcp --transport streamable-http

Requires Python 3.10+ and

Development Installation

For development or customization:

git clone https://github.com/taylorwilsdon/google_workspace_mcp.git
cd google_workspace_mcp
uv run main.py

Development Installation (For Contributors):

{
  "mcpServers": {
    "google_workspace": {
      "command": "uv",
      "args": [
        "run",
        "--directory",
        "/path/to/repo/google_workspace_mcp",
        "main.py"
      ],
      "env": {
        "GOOGLE_OAUTH_CLIENT_ID": "your-client-id",
        "GOOGLE_OAUTH_CLIENT_SECRET": "your-secret",
        "OAUTHLIB_INSECURE_TRANSPORT": "1"
      }
    }
  }
}

HTTP Mode (For debugging or web interfaces)

If you need to use HTTP mode with Claude Desktop:

{
  "mcpServers": {
    "google_workspace": {
      "command": "npx",
      "args": ["mcp-remote", "http://localhost:8000/mcp"]
    }
  }
}

Note: Make sure to start the server with

First-Time Authentication

The server uses Google Desktop OAuth for simplified authentication:

• No redirect URIs needed: Desktop OAuth clients handle authentication without complex callback URLs

• Automatic flow: The server manages the entire OAuth process transparently

• Transport-agnostic: Works seamlessly in both stdio and HTTP modes

When calling a tool:

1. Server returns authorization URL

2. Open URL in browser and authorize

3. Google provides an authorization code

4. Paste the code when prompted (or it's handled automatically)

5. Server completes authentication and retries your request

◆ Development

Project Structure

google_workspace_mcp/
├── auth/              # Authentication system with decorators
├── core/              # MCP server and utilities
├── g{service}/        # Service-specific tools
├── main.py            # Server entry point
├── client_secret.json # OAuth credentials (not committed)
└── pyproject.toml     # Dependencies

Adding New Tools

from auth.service_decorator import require_google_service

@require_google_service("drive", "drive_read")  # Service + scope group
async def your_new_tool(service, param1: str, param2: int = 10):
    """Tool description"""
    # service is automatically injected and cached
    result = service.files().list().execute()
    return result  # Return native Python objects

Architecture Highlights

• Service Caching: 30-minute TTL reduces authentication overhead

• Scope Management: Centralized in SCOPE_GROUPS for easy maintenance

• Error Handling: Native exceptions instead of manual error construction

• Multi-Service Support: @require_multiple_services() for complex tools

Credential Store System

The server includes an abstract credential store API and a default backend for managing Google OAuth credentials with support for multiple storage backends:

Features:

• Abstract Interface: CredentialStore base class defines standard operations (get, store, delete, list users)

• Local File Storage: LocalDirectoryCredentialStore implementation stores credentials as JSON files

• Configurable Storage: Environment variable GOOGLE_MCP_CREDENTIALS_DIR sets storage location

• Multi-User Support: Store and manage credentials for multiple Google accounts

• Automatic Directory Creation: Storage directory is created automatically if it doesn't exist

Configuration:

# Optional: Set custom credentials directory
export GOOGLE_MCP_CREDENTIALS_DIR="/path/to/credentials"

# Default locations (if GOOGLE_MCP_CREDENTIALS_DIR not set):
# - ~/.google_workspace_mcp/credentials (if home directory accessible)
# - ./.credentials (fallback)

Usage Example:

from auth.credential_store import get_credential_store

# Get the global credential store instance
store = get_credential_store()

# Store credentials for a user
store.store_credential("user@example.com", credentials)

# Retrieve credentials
creds = store.get_credential("user@example.com")

# List all users with stored credentials
users = store.list_users()

The credential store automatically handles credential serialization, expiry parsing, and provides error handling for storage operations.

⊠ Security

• Credentials: Never commit .env, client_secret.json or the .credentials/ directory to source control!

• OAuth Callback: Uses http://localhost:8000/oauth2callback for development (requires OAUTHLIB_INSECURE_TRANSPORT=1)

• Transport-Aware Callbacks: Stdio mode starts a minimal HTTP server only for OAuth, ensuring callbacks work in all modes

• Production: Use HTTPS & OAuth 2.1 and configure accordingly

• Network Exposure: Consider authentication when using mcpo over networks

• Scope Minimization: Tools request only necessary permissions

◆ Integration with Open WebUI

▶ Instant Start (No Config)

# Set credentials & launch in one command
GOOGLE_OAUTH_CLIENT_ID="your_id" \
GOOGLE_OAUTH_CLIENT_SECRET="your_secret" \
uvx mcpo --port 8000 --api-key "secret" \
-- uvx workspace-mcp

◆ Manual Configuration

1. Create config.json:

{
  "mcpServers": {
    "google_workspace": {
      "type": "streamablehttp",
      "url": "http://localhost:8000/mcp"
    }
  }
}

2. Start MCPO:

mcpo --port 8001 --config config.json

≡ Configure Open WebUI

1. Navigate to Settings → Connections → Tools

2. Click Add Tool and enter:

   • Server URL: http://localhost:8001/google_workspace

   • API Key: Your mcpo --api-key (if set)

3. Save - Google Workspace tools are now available!

≡ License

MIT License - see LICENSE file for details.

Validations: