# Mailersend

```json
{
  "name": "Mailersend",
  "slug": "mailersend",
  "url": "https://composio.dev/toolkits/mailersend",
  "markdown_url": "https://composio.dev/toolkits/mailersend.md",
  "logo_url": "https://logos.composio.dev/api/mailersend",
  "categories": [
    "collaboration & communication"
  ],
  "is_composio_managed": false,
  "updated_at": "2026-05-12T10:18:19.514Z"
}
```

![Mailersend logo](https://logos.composio.dev/api/mailersend)

## Description

Securely connect your AI agents and chatbots (Claude, ChatGPT, Cursor, etc) with Mailersend MCP or direct API to send transactional emails, check delivery status, manage recipients, and fetch analytics through natural language.

## Summary

MailerSend is a transactional email platform for developers to send, receive, and track emails via API. It provides reliable deliverability, analytics, and easy integration for your apps.

## Categories

- collaboration & communication

## Toolkit Details

- Tools: 23

## Images

- Logo: https://logos.composio.dev/api/mailersend

## Authentication

- **Api Key**
  - Type: `api_key`
  - Description: Api Key authentication for MailerSend.
  - Setup:
    - Configure Api Key credentials for MailerSend.
    - Use the credentials when creating an auth config in Composio.

## Suggested Prompts

- Add a new sending domain for my app
- List all SMTP users for our domain
- Check current API quota usage
- Show verified sending domains status

## Supported Tools

| Tool slug | Name | Description |
|---|---|---|
| `MAILERSEND_CREATE_DOMAIN` | Create Sending Domain | Tool to add a new sending domain to MailerSend. Use when you need to register and configure a domain before sending emails. |
| `MAILERSEND_CREATE_SMTP_USER` | Create SMTP User | Tool to create a new SMTP user. Use after domain setup to obtain SMTP credentials. |
| `MAILERSEND_CREATE_TOKEN` | Create API Token | Creates a new API token with specified scopes (permissions) for a domain. The token allows programmatic access to MailerSend API endpoints based on granted scopes. WARNING: The token value is only displayed once upon creation and cannot be retrieved later. |
| `MAILERSEND_CREATE_WEBHOOK` | Create Webhook | Tool to create a new webhook for a MailerSend domain. Use after you have a domain ID and need to receive event notifications like sent, delivered, opened, etc. |
| `MAILERSEND_DELETE_WEBHOOK` | Delete Webhook | Tool to delete an existing webhook. Use when the webhook is no longer needed. Returns empty response on successful deletion (HTTP 204). |
| `MAILERSEND_GET_API_QUOTA` | Get API Quota | Tool to retrieve current API usage quota. Use when monitoring API rate limits to avoid exceeding allowed calls. |
| `MAILERSEND_GET_DOMAIN` | Get Domain | Tool to retrieve detailed information about a specific sending domain in MailerSend. Returns domain verification status (DKIM, SPF, MX, tracking), settings (click/open tracking, paused status), and metadata (creation/update timestamps). Use this when you need to check if a domain is properly verified and configured for sending emails, or to review domain-specific tracking settings. Note: For detailed DNS record values, use the Get Domain DNS Records action. |
| `MAILERSEND_GET_DOMAIN_RECIPIENTS` | List Domain Recipients | Tool to list recipients for a domain. Use after obtaining the domain ID to view recipients with optional pagination. |
| `MAILERSEND_GET_DOMAINS` | Get sending domains | Retrieve a paginated list of all sending domains configured in your MailerSend account. Use this to: - View all domains available for sending emails - Check domain verification and DNS status - Filter by verification status to find verified or unverified domains - Review domain settings like tracking and sending preferences Returns domain details including verification status, DNS configuration, and tracking settings. |
| `MAILERSEND_GET_GENERAL_RESOURCES` | Get general API resources | Tool to retrieve general API resources and information. Use when you need an overview of all MailerSend endpoints before constructing specific calls. |
| `MAILERSEND_GET_IDENTITIES` | List Sender Identities | Retrieves a paginated list of sender identities configured in your MailerSend account. Sender identities are the email addresses or domains authorized to send emails through MailerSend. Each identity includes verification status, reply-to configuration, domain association, and optional personal notes. Use this tool to discover available sender identities before sending emails or to verify which identities are ready for use. Returns: Paginated list of identity objects with metadata including verification status, domain details, and navigation links for pagination. |
| `MAILERSEND_GET_MESSAGES` | Get sent messages | Tool to retrieve a paginated list of sent messages. Use after sending emails to view message logs. |
| `MAILERSEND_GET_RECIPIENTS` | Get email recipients | Tool to retrieve a list of email recipients. Use when you need to list and filter recipients by list ID or search term. |
| `MAILERSEND_GET_SMS_ACTIVITY` | Get SMS Activity | Tool to retrieve SMS activity logs. Use when you need to fetch delivery status and logs of sent SMS messages. |
| `MAILERSEND_GET_SMS_INBOUNDS` | Get SMS Inbounds | Retrieve inbound SMS route configurations. Inbound routes define rules for forwarding incoming SMS messages to webhook URLs based on message content filters. Use this action when you need to: - List all configured SMS inbound routes - Filter routes by SMS number or enabled status - Review webhook forwarding configurations and filter rules |
| `MAILERSEND_GET_SMS_MESSAGES` | List SMS Messages | Retrieves a paginated list of SMS messages sent through the MailerSend API. Returns message details including sender, recipients, content, status, and timestamps. Use this to review sent SMS messages and track their delivery status. Note: For detailed activity tracking with filters (date ranges, status, phone numbers), use the SMS Activity endpoint instead. |
| `MAILERSEND_GET_SMS_NUMBERS` | Get SMS Numbers | Tool to retrieve a paginated list of SMS phone numbers. Use after purchasing numbers to fetch available SMS numbers. |
| `MAILERSEND_GET_SMS_RECIPIENTS` | Get SMS recipients | Tool to retrieve a list of SMS recipients. Use when you need to list and paginate SMS recipients, optionally filtering by SMS number ID and/or recipient status. |
| `MAILERSEND_GET_SMTP_USERS` | Get SMTP users | Tool to retrieve a list of SMTP users. Use when you need to list and paginate SMTP users. |
| `MAILERSEND_GET_TEMPLATES` | Get email templates | Retrieves a paginated list of email templates from your MailerSend account. Use this tool when you need to: - List all available email templates - Filter templates by domain ID - Browse templates with pagination - Check template details like name, type, and creation date Returns template metadata including IDs, names, types, and timestamps. For full template content, use a separate get single template endpoint. |
| `MAILERSEND_GET_TOKENS` | Get API Tokens | Retrieves a paginated list of API tokens associated with your MailerSend account. Returns token details including ID, name, status, creation date, and assigned scopes/permissions. Requires 'tokens_full' scope. |
| `MAILERSEND_GET_USERS` | Get users | Tool to retrieve a list of users associated with your account. Use after authenticating with a valid API token. |
| `MAILERSEND_GET_WEBHOOKS` | List webhooks | Tool to retrieve a list of webhooks. Use when you need to list and paginate all configured webhooks, optionally filtering by domain. |

## Supported Triggers

None listed.

## Installation and MCP Setup

### Path 1: SDK Installation

#### Path 1, Step 1: Install Composio

Install the Composio SDK
```python
pip install composio_openai
```

```typescript
npm install @composio/openai
```

#### Path 1, Step 2: Initialize Composio and Create Tool Router Session

Import and initialize Composio client, then create a Tool Router session
```python
from openai import OpenAI
from composio import Composio
from composio_openai import OpenAIResponsesProvider

composio = Composio(provider=OpenAIResponsesProvider())
openai = OpenAI()
session = composio.create(user_id='your-user-id')
```

```typescript
import OpenAI from 'openai';
import { Composio } from '@composio/core';
import { OpenAIResponsesProvider } from '@composio/openai';

const composio = new Composio({
  provider: new OpenAIResponsesProvider(),
});
const openai = new OpenAI({});
const session = await composio.create('your-user-id');
```

#### Path 1, Step 3: Execute Mailersend Tools via Tool Router with Your Agent

Get tools from Tool Router session and execute Mailersend actions with your Agent
```python
tools = session.tools
response = openai.responses.create(
  model='gpt-4.1',
  tools=tools,
  input=[{
    'role': 'user',
    'content': 'Send a welcome email to a new user'
  }]
)
result = composio.provider.handle_tool_calls(
  response=response,
  user_id='your-user-id'
)
print(result)
```

```typescript
const tools = session.tools;
const response = await openai.responses.create({
  model: 'gpt-4.1',
  tools: tools,
  input: [{
    role: 'user',
    content: 'Send a welcome email to a new user'
  }],
});
const result = await composio.provider.handleToolCalls(
  'your-user-id',
  response.output
);
console.log(result);
```

### Path 2: MCP Server Setup

#### Path 2, Step 1: Install Composio

Install the Composio SDK and Claude Agent SDK
```python
pip install composio claude-agent-sdk
```

```typescript
npm install @composio/core ai @ai-sdk/openai @ai-sdk/mcp
```

#### Path 2, Step 2: Create Tool Router Session

Initialize the Composio client and create a Tool Router session
```python
from composio import Composio
from claude_agent_sdk import ClaudeSDKClient, ClaudeAgentOptions

composio = Composio(api_key='your-composio-api-key')
session = composio.create(user_id='your-user-id')
url = session.mcp.url
```

```typescript
import { Composio } from '@composio/core';

const composio = new Composio({ apiKey: 'your-api-key' });

console.log("Creating Tool Router session...");
const { mcp } = await composio.create('your-user-id');
console.log(`Tool Router session created: ${mcp.url}`);
```

#### Path 2, Step 3: Connect to AI Agent

Use the MCP server with your AI agent
```python
import asyncio

options = ClaudeAgentOptions(
    permission_mode='bypassPermissions',
    mcp_servers={
        'tool_router': {
            'type': 'http',
            'url': url,
            'headers': {
                'x-api-key': 'your-composio-api-key'
            }
        }
    },
    system_prompt='You are a helpful assistant with access to Mailersend tools.',
    max_turns=10
)

async def main():
    async with ClaudeSDKClient(options=options) as client:
        await client.query('Send a transactional email to support@example.com with subject "Order Update"')
        async for message in client.receive_response():
            if hasattr(message, 'content'):
                for block in message.content:
                    if hasattr(block, 'text'):
                        print(block.text)

asyncio.run(main())
```

```typescript
import { openai } from '@ai-sdk/openai';
import { experimental_createMCPClient as createMCPClient } from '@ai-sdk/mcp';
import { generateText, stepCountIs } from 'ai';

const client = await createMCPClient({
  transport: {
    type: 'http',
    url: mcp.url,
    headers: { 'x-api-key': 'your-composio-api-key' }
  }
});

const tools = await client.tools();

const { text } = await generateText({
  model: openai('gpt-4o'),
  tools,
  messages: [{ role: 'user', content: 'Send a transactional email to support@example.com with subject "Order Update"' }],
  stopWhen: stepCountIs( 5 )
});

console.log(`Agent: ${text}`);
```

## Why Use Composio?

### 1. AI Native Mailersend Integration

- Supports both Mailersend MCP and direct API based integrations
- Structured, LLM-friendly schemas for reliable tool execution
- Rich coverage for sending, fetching, and querying Mailersend emails

### 2. Managed Auth

- Built-in API key handling and secure storage
- Central place to manage, scope, and rotate Mailersend access
- Per user and per environment credentials instead of hard-coded keys

### 3. Agent Optimized Design

- Tools are tuned using real error and success rates to improve reliability over time
- Comprehensive execution logs so you always know what ran, when, and on whose behalf

### 4. Enterprise Grade Security

- Fine-grained RBAC so you control which agents and users can access Mailersend
- Scoped, least privilege access to Mailersend resources
- Full audit trail of agent actions to support review and compliance

## Use Mailersend with any AI Agent Framework

Choose a framework you want to connect Mailersend with:

- [OpenAI Agents SDK](https://composio.dev/toolkits/mailersend/framework/open-ai-agents-sdk)
- [Claude Agent SDK](https://composio.dev/toolkits/mailersend/framework/claude-agents-sdk)
- [Claude Code](https://composio.dev/toolkits/mailersend/framework/claude-code)
- [Claude Cowork](https://composio.dev/toolkits/mailersend/framework/claude-cowork)
- [Codex](https://composio.dev/toolkits/mailersend/framework/codex)
- [OpenClaw](https://composio.dev/toolkits/mailersend/framework/openclaw)
- [Hermes](https://composio.dev/toolkits/mailersend/framework/hermes-agent)
- [Google ADK](https://composio.dev/toolkits/mailersend/framework/google-adk)
- [LangChain](https://composio.dev/toolkits/mailersend/framework/langchain)
- [Vercel AI SDK](https://composio.dev/toolkits/mailersend/framework/ai-sdk)
- [Mastra AI](https://composio.dev/toolkits/mailersend/framework/mastra-ai)
- [LlamaIndex](https://composio.dev/toolkits/mailersend/framework/llama-index)
- [CrewAI](https://composio.dev/toolkits/mailersend/framework/crew-ai)
- [Pydantic AI](https://composio.dev/toolkits/mailersend/framework/pydantic-ai)
- [AutoGen](https://composio.dev/toolkits/mailersend/framework/autogen)

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- [Microsoft teams](https://composio.dev/toolkits/microsoft_teams) - Microsoft Teams is a collaboration platform that combines chat, meetings, and file sharing within Microsoft 365. It keeps distributed teams connected and productive through seamless virtual communication.
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- [2chat](https://composio.dev/toolkits/_2chat) - 2chat is an API platform for WhatsApp and multichannel text messaging. It streamlines chat automation, group management, and real-time messaging for developers.
- [Agent mail](https://composio.dev/toolkits/agent_mail) - Agent mail provides AI agents with dedicated email inboxes for sending, receiving, and managing emails. It empowers agents to communicate autonomously with people, services, and other agents—no human intervention needed.
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- [Dailybot](https://composio.dev/toolkits/dailybot) - DailyBot streamlines team collaboration with chat-based standups, reminders, and polls. It keeps work flowing smoothly in your favorite messaging platforms.
- [Dialmycalls](https://composio.dev/toolkits/dialmycalls) - Dialmycalls is a mass notification service for sending voice and text messages to contacts. It helps teams and organizations quickly broadcast urgent alerts and updates.
- [Dialpad](https://composio.dev/toolkits/dialpad) - Dialpad is a cloud-based business phone and contact center system for teams. It unifies voice, video, messaging, and meetings across your devices.
- [Discord](https://composio.dev/toolkits/discord) - Discord is a real-time messaging and VoIP platform for communities and teams. It lets users chat, share media, and collaborate across public and private channels.
- [Discordbot](https://composio.dev/toolkits/discordbot) - Discordbot is an automation tool for Discord servers that handles moderation, messaging, and user engagement. It helps communities run smoothly by automating routine and complex tasks.
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## Frequently Asked Questions

### Do I need my own developer credentials to use Mailersend with Composio?

Yes, Mailersend requires you to configure your own API key. Once set up, Composio handles secure credential storage and API request handling for you.

### Can I use multiple toolkits together?

Yes! Composio's Tool Router enables agents to use multiple toolkits. [Learn more](https://docs.composio.dev/tool-router/overview).

### Is Composio secure?

Composio is SOC 2 and ISO 27001 compliant with all data encrypted in transit and at rest. [Learn more](https://trust.composio.dev).

### What if the API changes?

Composio maintains and updates all toolkit integrations automatically, so your agents always work with the latest API versions.

---
[See all toolkits](https://composio.dev/toolkits) · [Composio docs](https://docs.composio.dev/llms.txt)