MCP IMAP Server

A Model Context Protocol (MCP) server that enables Claude and other LLM applications to read emails via the IMAP protocol. This server provides secure, read-only access to email accounts from popular providers like Gmail, Outlook, Yahoo, and custom IMAP servers.

Features

• 🔐 Secure Authentication: Support for username/password authentication with secure credential handling

• 📧 Email Operations: Search, read, and manage emails with comprehensive filtering options

• 📁 Folder Management: List and navigate email folders/mailboxes

• 🏷️ Email Status: Mark emails as read/unread

• 🔍 Advanced Search: Search by sender, subject, date range, content, and read status

• 🌐 Provider Support: Pre-configured for Gmail, Outlook, Yahoo, iCloud, and custom IMAP servers

• 🛡️ Security First: Read-only access, no email sending or deletion capabilities

• ⚡ Performance: Efficient connection pooling and error handling

Quick Start

Installation

git clone <repository-url>
cd mcp-imap-server
npm install
npm run build

Configuration

Create a .env file in the project root:

# Required: IMAP server configuration
IMAP_HOST=imap.gmail.com
IMAP_PORT=993
IMAP_USER=your-email@gmail.com
IMAP_PASSWORD=your-app-password
IMAP_TLS=true

# Optional: Connection settings
IMAP_AUTH_TIMEOUT=3000
IMAP_CONN_TIMEOUT=10000
IMAP_KEEPALIVE_INTERVAL=10000
IMAP_IDLE_INTERVAL=300000
IMAP_FORCE_NOOP=false

Popular Email Provider Settings

Gmail

IMAP_HOST=imap.gmail.com
IMAP_PORT=993
IMAP_TLS=true

Outlook/Hotmail

IMAP_HOST=outlook.office365.com
IMAP_PORT=993
IMAP_TLS=true

Yahoo Mail

IMAP_HOST=imap.mail.yahoo.com
IMAP_PORT=993
IMAP_TLS=true

iCloud Mail

IMAP_HOST=imap.mail.me.com
IMAP_PORT=993
IMAP_TLS=true

Running the Server

# Development mode
npm run dev

# Production mode
npm run build
npm start

MCP Tools

The server exposes the following tools to MCP clients:

search_emails

Search for emails based on various criteria.

Parameters:

• sender (optional): Filter by sender email address or name

• subject (optional): Filter by subject line (partial match)

• dateFrom (optional): Start date for date range filter (ISO format: YYYY-MM-DD)

• dateTo (optional): End date for date range filter (ISO format: YYYY-MM-DD)

• content (optional): Search within email content/body text

• unread (optional): Filter by read status (true for unread only, false for read only)

• folder (optional): Folder to search in (defaults to INBOX)

• limit (optional): Maximum number of emails to return (1-100)

Example:

{
  "name": "search_emails",
  "arguments": {
    "sender": "notifications@github.com",
    "unread": true,
    "limit": 10
  }
}

get_email

Retrieve the full content of a specific email by its message ID.

Parameters:

• messageId (required): The message ID or UID of the email to retrieve

• folder (optional): Folder containing the email (defaults to INBOX)

Example:

{
  "name": "get_email",
  "arguments": {
    "messageId": "12345",
    "folder": "INBOX"
  }
}

list_folders

List all available email folders/mailboxes in the account.

Parameters:

• includeSpecial (optional): Include special folders like Sent, Drafts, etc.

Example:

{
  "name": "list_folders",
  "arguments": {
    "includeSpecial": true
  }
}

get_recent_emails

Get the most recent emails from a specific folder.

Parameters:

• folder (optional): Folder to get emails from (defaults to INBOX)

• limit (optional): Number of recent emails to retrieve (1-50, default: 10)

• unreadOnly (optional): Only return unread emails

Example:

{
  "name": "get_recent_emails",
  "arguments": {
    "folder": "INBOX",
    "limit": 5,
    "unreadOnly": true
  }
}

mark_as_read

Mark an email as read or unread.

Parameters:

• messageId (required): The message ID or UID of the email to mark

• folder (optional): Folder containing the email (defaults to INBOX)

• read (optional): Mark as read (true) or unread (false). Default: true

Example:

{
  "name": "mark_as_read",
  "arguments": {
    "messageId": "12345",
    "read": true
  }
}

Security Considerations

Email Provider Setup

Gmail

1. Enable 2-factor authentication

2. Generate an App Password (not your regular password)

3. Use the App Password as IMAP_PASSWORD

Outlook/Hotmail

1. Enable 2-factor authentication

2. Generate an App Password

3. Use the App Password as IMAP_PASSWORD

Other Providers

Consult your email provider's documentation for IMAP access and app password setup.

Best Practices

• Never log credentials: The server is designed to never log sensitive information

• Use app passwords: Always use app-specific passwords, never your main account password

• Read-only access: The server only provides read operations for security

• Secure storage: Store credentials securely and never commit them to version control

• Network security: Always use TLS/SSL connections (enabled by default)

Development

Project Structure

src/
├── config/          # Configuration management
├── services/        # IMAP connection and management
├── tools/           # MCP tool implementations
├── types/           # TypeScript type definitions
└── index.ts         # Main server entry point

Available Scripts

npm run build        # Build TypeScript to JavaScript
npm run dev          # Run in development mode with auto-reload
npm start            # Run the built server
npm test             # Run tests
npm run lint         # Lint the code
npm run typecheck    # Type check without building
npm run clean        # Clean build directory

Adding New Tools

1. Define types in src/types/index.ts

2. Add Zod validation schema

3. Implement the tool logic in src/tools/index.ts

4. Register the tool in src/index.ts

Error Handling

The server includes comprehensive error handling for:

• Authentication failures: Clear messages for invalid credentials

• Connection issues: Timeout and network error handling

• IMAP protocol errors: Detailed error messages for debugging

• Validation errors: Input validation with helpful error messages

Troubleshooting

Common Issues

1. Authentication Failed

   • Verify your email and app password are correct

   • Ensure 2FA is enabled and you're using an app password

   • Check if IMAP is enabled in your email provider settings

2. Connection Timeout

   • Verify the IMAP host and port settings

   • Check your firewall and network settings

   • Try increasing the connection timeout values

3. TLS/SSL Errors

   • Ensure IMAP_TLS=true for secure connections

   • Verify your email provider supports the specified port with TLS

Debug Mode

Set NODE_ENV=development to enable debug logging:

NODE_ENV=development npm run dev

Contributing

1. Fork the repository

2. Create a feature branch

3. Make your changes with proper tests

4. Ensure all tests pass and code is properly typed

5. Submit a pull request

License

MIT License - see LICENSE file for details.

Support

For issues and questions:

1. Check the troubleshooting section above

2. Review your email provider's IMAP documentation

3. Open an issue on GitHub with detailed error messages and configuration (without credentials)