What is Mailtrap Mcp

mailtrap-mcp is an official MCP server that facilitates the sending of transactional emails through Mailtrap, a service designed for email testing and development.

Use cases

Use cases for mailtrap-mcp include sending test emails during application development, notifying users about updates or events, and automating email communications in a controlled environment.

How to use

To use mailtrap-mcp, configure the Claude Desktop settings by editing the configuration file to include your Mailtrap API token and default sender email. Once set up, you can instruct the agent to send emails using natural language commands.

Key features

Key features of mailtrap-mcp include seamless integration with Mailtrap for email testing, the ability to send transactional emails, and easy configuration through Claude Desktop.

Where to use

mailtrap-mcp is ideal for developers and teams working on applications that require email functionalities, particularly in testing environments where email delivery needs to be simulated without sending real emails.

MCP Mailtrap Server

An MCP server that provides a tool for sending transactional emails via Mailtrap

Quick Install

Setup

Claude Desktop or Cursor

Add the following configuration:

{
  "mcpServers": {
    "mailtrap": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-mailtrap"
      ],
      "env": {
        "MAILTRAP_API_TOKEN": "your_mailtrap_api_token",
        "DEFAULT_FROM_EMAIL": "[email protected]"
      }
    }
  }
}

If you are using asdf for managing Node.js you must use absolute path to executable (example for Mac)

{
  "mcpServers": {
    "mailtrap": {
      "command": "/Users/<username>/.asdf/shims/npx",
      "args": [
        "-y",
        "mcp-mailtrap"
      ],
      "env": {
        "PATH": "/Users/<username>/.asdf/shims:/usr/bin:/bin",
        "ASDF_DIR": "/opt/homebrew/opt/asdf/libexec",
        "ASDF_DATA_DIR": "/Users/<username>/.asdf",
        "ASDF_NODEJS_VERSION": "20.6.1",
        "MAILTRAP_API_TOKEN": "your_mailtrap_api_token",
        "DEFAULT_FROM_EMAIL": "[email protected]"
      }
    }
  }
}

Claude Desktop config file location

Mac: ~/Library/Application Support/Claude/claude_desktop_config.json

Windows: %APPDATA%\Claude\claude_desktop_config.json

Cursor config file location

Mac: ~/.cursor/mcp.json

Windows: %USERPROFILE%\.cursor\mcp.json

VS Code

Manually changing config

Run in Command Palette: Preferences: Open User Settings (JSON)

Then, in the settings file, add the following configuration:

{
  "mcp": {
    "servers": {
      "mailtrap": {
        "command": "npx",
        "args": [
          "-y",
          "mcp-mailtrap"
        ],
        "env": {
          "MAILTRAP_API_TOKEN": "your_mailtrap_api_token",
          "DEFAULT_FROM_EMAIL": "[email protected]"
        }
      }
    }
  }
}

[!TIP]
Don’t forget to restart your MCP server after changing the “env” section.

Usage

Once configured, you can ask agent to send emails, for example:

• “Send an email to [email protected] with the subject ‘Meeting Tomorrow’ and a friendly reminder about our upcoming meeting.”
• “Email [email protected] about the project update, and CC the team at [email protected]”

Available Tools

send-email

Sends a transactional email through Mailtrap.

Parameters:

• to (required): Email address of the recipient
• subject (required): Email subject line
• from (optional): Email address of the sender, if not provided “DEFAULT_FROM_EMAIL” will be used
• text (optional): Email body text, require if “html” is empty
• html (optional): HTML version of the email body, required if “text” is empty
• cc (optional): Array of CC recipient email addresses
• bcc (optional): Array of BCC recipient email addresses
• category (optional): Email category for tracking

Development

1. Clone the repository:

git clone https://github.com/railsware/mailtrap-mcp.git
cd mailtrap-mcp

2. Install dependencies:

npm install

Configuration with Claude Desktop or Cursor

[!TIP]
See the location of the config file in the Setup section.

Add the following configuration:

{
  "mcpServers": {
    "mailtrap": {
      "command": "node",
      "args": [
        "/path/to/mailtrap-mcp/dist/index.js"
      ],
      "env": {
        "MAILTRAP_API_TOKEN": "your_mailtrap_api_token",
        "DEFAULT_FROM_EMAIL": "[email protected]"
      }
    }
  }
}

If you are using asdf for managing Node.js you should use absolute path to executable:

(example for Mac)

{
  "mcpServers": {
    "mailtrap": {
      "command": "/Users/<username>/.asdf/shims/node",
      "args": [
        "/path/to/mailtrap-mcp/dist/index.js"
      ],
      "env": {
        "PATH": "/Users/<username>/.asdf/shims:/usr/bin:/bin",
        "ASDF_DIR": "/opt/homebrew/opt/asdf/libexec",
        "ASDF_DATA_DIR": "/Users/<username>/.asdf",
        "ASDF_NODEJS_VERSION": "20.6.1",
        "MAILTRAP_API_TOKEN": "your_mailtrap_api_token",
        "DEFAULT_FROM_EMAIL": "[email protected]"
      }
    }
  }
}

VS Code

[!TIP]
See the location of the config file in the Setup section.

{
  "mcp": {
    "servers": {
      "mailtrap": {
        "command": "node",
        "args": [
          "/path/to/mailtrap-mcp/dist/index.js"
        ],
        "env": {
          "MAILTRAP_API_TOKEN": "your_mailtrap_api_token",
          "DEFAULT_FROM_EMAIL": "[email protected]"
        }
      }
    }
  }
}

Testing

You can test the server using the MCP Inspector:

npm run dev

Contributing

Bug reports and pull requests are welcome on GitHub. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the code of conduct.

License

The package is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the Mailtrap project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.