Gmail MCP Server

A custom MCP server for sending emails through Gmail.

Features

• Send custom emails (App Password or OAuth2)

• Send professional introduction emails

• Gmail configuration validation

• Support for both App Password and OAuth2 authentication

• HTML and text email support

• List Gmail labels (OAuth2)

• List unread emails with optional search query (OAuth2)

• Retrieve a full email by ID (OAuth2)

• Archive (remove from INBOX) or trash an email (OAuth2)

• Simple template engine (Mustache) for reusable email content

• Send email from template with variable substitution

Quick Setup

1. Install Dependencies

npm install

2. Configure Gmail Authentication

Option A: App Password (Recommended for simplicity)

1. Go to your Google Account settings: https://myaccount.google.com/

2. Navigate to Security > 2-Step Verification (must be enabled)

3. Go to Security > 2-Step Verification > App passwords

4. Generate a new app password for "Mail"

5. Copy the 16-character password

6. Update your .env file:

   GMAIL_USER = example@example.com
   GMAIL_AUTH_METHOD=app_password
   GMAIL_APP_PASSWORD=your_16_character_password_here

Option B: OAuth2 (More secure, requires Google Cloud setup)

1. Create a project in Google Cloud Console

2. Enable Gmail API

3. Create OAuth2 credentials

4. Get refresh token

5. Update .env with OAuth2 credentials

GMAIL_CLIENT_ID=xxx
GMAIL_CLIENT_SECRET=xxx
GMAIL_REDIRECT_URI=https://developers.google.com/oauthplayground
GMAIL_REFRESH_TOKEN=xxx

Note: Reading/listing/archiving/deleting emails REQUIRES OAuth2. Sending can still work with App Password only.

3. Test the Server

npm start

4. Add to Claude MCP Config

Add this to your Claude MCP configuration file:

{
  "mcpServers": {
    "gmail": {
      "command": "node",
      "args": ["/Users/user/Desktop/gmail-mcp/index.js"],
      "cwd": "/Users/user/Desktop/gmail-mcp"
    }
  }
}

Usage Examples

Once configured in Claude:

"Send an introduction email to abc@gmail.com"
"Check if my Gmail configuration is working"
"Send an email to someone@example.com with subject 'Hello' and body 'Test message'"
"List unread emails"
"List unread emails with query 'from:recruiter'"
"Get email with id 18c5b9b1a2e3a4b5"
"Archive email with id 18c5b9b1a2e3a4b5"
"Delete email with id 18c5b9b1a2e3a4b5"
"List email templates"
"Send a template email to user@example.com using template introduction with variables {\"name\":\"Nasir\", \"recipientName\":\"Alex\"}"

### Template Emails

Templates live in the `templates/` directory. Each template is a `.txt` file and can optionally start with a `Subject:` line. Mustache-style placeholders (`{{variable}}`) are replaced using the `variables` object you pass.

Example command via MCP:

Send a template email to user@example.com using template follow_up with variables {"name":"Nasir","recipientName":"Alex","topic":"our earlier discussion"}