useSend MCP Server

An MCP (Model Context Protocol) server that enables LLMs to interact with the useSend email platform. Provides comprehensive tools for sending emails, managing contacts, running campaigns, and configuring domains.

Features

• Email Operations: Send single or batch emails, list and retrieve emails, cancel or reschedule scheduled emails
• Contact Book Management: Create, update, and manage contact books
• Contact Management: Full CRUD operations for contacts within contact books
• Campaign Management: Create, schedule, pause, and resume email campaigns
• Domain Configuration: List, create, verify, and manage sending domains

Quick Start

Install from npm

npm install -g usesend-mcp-server

Or clone and build

git clone https://github.com/flyingwebie/usesend-mcp-server.git
cd usesend-mcp-server
npm install
npm run build

Get Your API Key

Get your API key from the useSend dashboard. Keys start with us_.

IDE Integration Guides

Claude Code

Add to ~/.claude/claude_desktop_config.json:

{
  "mcpServers": {
    "usesend": {
      "command": "npx",
      "args": ["-y", "usesend-mcp-server"],
      "env": {
        "USESEND_BASE_URL": "https://app.usesend.com/api/",
        "USESEND_API_KEY": "us_your_api_key_here",
        "USESEND_DEFAULT_FROM": "noreply@yourdomain.com"
      }
    }
  }
}

Or if installed locally:

{
  "mcpServers": {
    "usesend": {
      "command": "node",
      "args": ["/path/to/usesend-mcp-server/dist/index.js"],
      "env": {
        "USESEND_BASE_URL": "https://app.usesend.com/api/",
        "USESEND_API_KEY": "us_your_api_key_here",
        "USESEND_DEFAULT_FROM": "noreply@yourdomain.com"
      }
    }
  }
}

Claude Desktop

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "usesend": {
      "command": "npx",
      "args": ["-y", "usesend-mcp-server"],
      "env": {
        "USESEND_BASE_URL": "https://app.usesend.com/api/",
        "USESEND_API_KEY": "us_your_api_key_here",
        "USESEND_DEFAULT_FROM": "noreply@yourdomain.com"
      }
    }
  }
}

Cursor

Add to .cursor/mcp.json in your project root:

{
  "mcpServers": {
    "usesend": {
      "command": "npx",
      "args": ["-y", "usesend-mcp-server"],
      "env": {
        "USESEND_BASE_URL": "https://app.usesend.com/api/",
        "USESEND_API_KEY": "us_your_api_key_here",
        "USESEND_DEFAULT_FROM": "noreply@yourdomain.com"
      }
    }
  }
}

Or configure globally in Cursor Settings > MCP Servers.

VS Code with Cline Extension

Add to your VS Code settings.json:

{
  "cline.mcpServers": {
    "usesend": {
      "command": "npx",
      "args": ["-y", "usesend-mcp-server"],
      "env": {
        "USESEND_BASE_URL": "https://app.usesend.com/api/",
        "USESEND_API_KEY": "us_your_api_key_here",
        "USESEND_DEFAULT_FROM": "noreply@yourdomain.com"
      }
    }
  }
}

Windsurf

Add to your Windsurf MCP configuration:

{
  "mcpServers": {
    "usesend": {
      "command": "npx",
      "args": ["-y", "usesend-mcp-server"],
      "env": {
        "USESEND_BASE_URL": "https://app.usesend.com/api/",
        "USESEND_API_KEY": "us_your_api_key_here",
        "USESEND_DEFAULT_FROM": "noreply@yourdomain.com"
      }
    }
  }
}

OpenAI Codex CLI

Set environment variables before running:

export USESEND_API_KEY="us_your_api_key_here"
export USESEND_BASE_URL= "https://app.usesend.com/api/"
export USESEND_DEFAULT_FROM= "noreply@yourdomain.com"
npx usesend-mcp-server

MCP Inspector (Testing)

USESEND_API_KEY=us_your_api_key USESEND_BASE_URL= "https://app.usesend.com/api/" USESEND_DEFAULT_FROM= "noreply@yourdomain.com" npx @modelcontextprotocol/inspector npx usesend-mcp-server

Example Prompts

Once configured, you can use natural language to interact with useSend:

Sending Emails

"Send an email to john@example.com with subject 'Meeting Tomorrow' and let them know the meeting is at 3pm"

"Send a batch of welcome emails to these addresses: alice@test.com, bob@test.com"

Managing Contact Books

"List all my contact books"

"Create a new contact book called 'VIP Customers' with a star emoji"

"How many contacts are in my Newsletter Subscribers book?"

Managing Contacts

"List all contacts in my newsletter contact book"

"Add a new contact jane@example.com with name Jane Smith to the marketing list"

"Update the contact john@example.com to set their company as Acme Inc"

Campaign Operations

"Create a new campaign called 'Summer Sale' with subject 'Big Discounts Inside'"

"Schedule the Summer Sale campaign to send tomorrow at 9am"

"Pause the active newsletter campaign"

"Show me the metrics for my last campaign"

Domain Management

"List all my verified sending domains"

"Add a new domain notifications.mycompany.com"

"Check the DNS verification status for mycompany.com"

"What DNS records do I need to add for my new domain?"

Available Tools

Email Tools (6)

Tool	Description
usesend_send_email	Send a single transactional email
usesend_list_emails	List emails with filtering and pagination
usesend_get_email	Get detailed information about a specific email
usesend_batch_send_emails	Send up to 100 emails in one request
usesend_cancel_email	Cancel a scheduled email
usesend_update_email_schedule	Update the scheduled time for an email

Contact Book Tools (5)

Tool	Description
usesend_list_contact_books	List all contact books
usesend_get_contact_book	Get contact book details
usesend_create_contact_book	Create a new contact book
usesend_update_contact_book	Update contact book properties
usesend_delete_contact_book	Delete a contact book

Contact Tools (6)

Tool	Description
usesend_list_contacts	List contacts in a contact book
usesend_get_contact	Get a specific contact by ID
usesend_create_contact	Create a new contact
usesend_update_contact	Update an existing contact
usesend_upsert_contact	Create or update a contact
usesend_delete_contact	Delete a contact

Campaign Tools (5)

Tool	Description
usesend_create_campaign	Create a new email campaign
usesend_get_campaign	Get campaign details and metrics
usesend_schedule_campaign	Schedule a campaign for sending
usesend_pause_campaign	Pause an active campaign
usesend_resume_campaign	Resume a paused campaign

Domain Tools (5)

Tool	Description
usesend_list_domains	List all configured domains
usesend_get_domain	Get domain details with DNS records
usesend_create_domain	Register a new sending domain
usesend_verify_domain	Verify domain ownership
usesend_delete_domain	Delete a domain

Configuration

Variable	Required	Description
USESEND_API_KEY	Yes	Your useSend API key (starts with us_)
USESEND_BASE_URL	No	Custom API URL (default: https://app.usesend.com/api)
USESEND_DEFAULT_FROM	No	Default sender email address for sending emails

Default Sender Address

Setting USESEND_DEFAULT_FROM allows you to send emails without specifying the from address each time. This is useful when you always send from the same address.

# Example: Set default sender
export USESEND_DEFAULT_FROM="noreply@yourdomain.com"

With this set, you can simply say:

"Send an email to john@example.com with subject 'Hello'"

Instead of:

"Send an email from noreply@yourdomain.com to john@example.com with subject 'Hello'"

Tool Parameters

Response Format

Most read operations support a response_format parameter:

• markdown (default): Human-readable formatted output
• json: Raw JSON for programmatic processing

Pagination

List operations support:

• page: Page number (default: 1)
• limit: Results per page (default: 50, max: 100)

API Examples

Send an Email

Tool: usesend_send_email
Parameters:
  to: "recipient@example.com"
  from: "noreply@yourdomain.com"
  subject: "Hello from useSend"
  html: "<h1>Welcome!</h1><p>This is a test email.</p>"
  text: "Welcome! This is a test email."

Create a Contact

Tool: usesend_create_contact
Parameters:
  contactBookId: "cb_123456"
  email: "john@example.com"
  firstName: "John"
  lastName: "Doe"
  properties: {"company": "Acme Inc", "role": "Developer"}

Schedule a Campaign

Tool: usesend_schedule_campaign
Parameters:
  campaignId: "cmp_123456"
  scheduledAt: "2024-01-15T09:00:00Z"
  batchSize: 1000

Check Domain Status

Tool: usesend_get_domain
Parameters:
  domainId: 123
  response_format: "markdown"

Development

# Install dependencies
npm install

# Build
npm run build

# Development mode (watch)
npm run dev

# Type check
npm run typecheck

# Test with MCP Inspector
USESEND_API_KEY=us_test npx @modelcontextprotocol/inspector node dist/index.js

Project Structure

usesend-mcp-server/
├── src/
│   ├── index.ts              # Server entry point
│   ├── constants.ts          # Configuration and enums
│   ├── types.ts              # TypeScript interfaces
│   ├── client/
│   │   └── usesend-client.ts # API client with auth
│   ├── tools/
│   │   ├── index.ts          # Tool registration
│   │   ├── emails.ts         # Email tools
│   │   ├── contactBooks.ts   # Contact book tools
│   │   ├── contacts.ts       # Contact tools
│   │   ├── campaigns.ts      # Campaign tools
│   │   └── domains.ts        # Domain tools
│   ├── schemas/
│   │   ├── emails.ts         # Email Zod schemas
│   │   ├── contactBooks.ts   # Contact book Zod schemas
│   │   ├── contacts.ts       # Contact Zod schemas
│   │   ├── campaigns.ts      # Campaign Zod schemas
│   │   └── domains.ts        # Domain Zod schemas
│   └── utils/
│       ├── error-handler.ts  # Error handling
│       └── formatters.ts     # Response formatting
├── dist/                     # Compiled JavaScript
├── package.json
├── tsconfig.json
└── README.md

Error Handling

The server provides actionable error messages for common issues:

Code	Description	Solution
401	Invalid API key	Check USESEND_API_KEY
403	Permission denied	Verify API key permissions
404	Resource not found	Check the resource ID
409	Idempotency conflict	Use a different key
429	Rate limit exceeded	Wait and retry

License

MIT