Email MCP Server by Sidemail

MCP Server – Send & manage emails, contacts and sending domains

Sidemail MCP server enables you to programmatically send and manage transactional emails, contacts, sending domains, and Messenger features – right from MCP agent mode in VS Code, Claude, Cursor, and other MCP clients.

What is MCP? Model Context Protocol (MCP) is a new open standard that makes it easier for AI systems to connect with external data and services. MCP acts a bit like an API for AI models – it provides a standard “language” for AI programs to access tools or data from the outside world. Learn more in our explanation article.

MCP server features

• Manage sending domains

• Test sending transactional emails

• Manage contacts and groups

• Create, update, and delete Messenger drafts

• Query sent emails and contacts

MCP Server Tools

Domains

• list-domains: List all sending domains

• create-domain: Add a new sending domain

• delete-domain: Remove a sending domain

Example – Adding a new sending domain:

Messenger

• list-messenger-drafts: List Messenger drafts

• get-messenger-draft: Get Messenger draft by ID

• create-messenger-draft: Create a Messenger draft

• update-messenger-draft: Update a Messenger draft

• delete-messenger-draft: Delete a Messenger draft

Example – Writing a product update email:

Groups

• list-groups: List all contact groups

• create-group: Create a new contact group

• update-group: Update a contact group

Contacts

• create-or-update-contact: Create or update a contact

• query-contacts: Query contacts with filters

• find-contact: Find a contact by email

• delete-contact: Delete a contact

Emails

• send-email: Send a transactional email (testing only)

• query-emails: Query sent emails

More resources

• Github repository: sidemail/sidemail-mcp-server

• NPM package: @sidemail/mcp

• Features overview

Prerequisites

• Node.js v18 or newer

• Sidemail API Key

Microsoft VS Code setup (assisted)

• Open the Command Palette (Ctrl/Cmd + Shift + P).

• Type “MCP: Add Server…” and select it.

• Select "NPM Package".

• Enter @sidemail/mcp and confirm it.

• Confirm the installation.

• Enter your Sidemail API key and confirm it.

Microsoft VS Code setup (manual)

Alternatively, you can install it manually by modifying the mcp.json configuration file.

• Open the Command Palette (Ctrl/Cmd + Shift + P).

• Type “MCP: Open User Configuration” and select it.

• Add the configuration below and save changes.

{
 "servers": {
 "sidemail-mcp": {
 "type": "stdio",
 "command": "npx",
 "args": ["-y", "@sidemail/mcp"],
 "env": {
 "SIDEMAIL_API_KEY": "${input:sidemail-key}"
 }
 }
 },
 "inputs": [
 {
 "type": "promptString",
 "id": "sidemail-key",
 "description": "Sidemail API Key",
 "password": true
 }
 ]
}

Claude Desktop setup

Edit (or create) the config file:

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

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

• Linux: ~/.config/Claude/claude_desktop_config.json

{
 "mcpServers": {
 "sidemail": {
 "command": "npx",
 "args": ["-y", "@sidemail/mcp"],
 "env": { "SIDEMAIL_API_KEY": "your-key" }
 }
 }
}

Cursor setup

Create or edit ~/.cursor/mcp.json:

CLI Usage

npx @sidemail/mcp