How to integrate Enginemailer MCP with Claude Agent SDK

This guide walks you through connecting Enginemailer to the Claude Agent SDK using the Composio tool router. By the end, you'll have a working Enginemailer agent that can add new subscriber to newsletter list, pause tomorrow's scheduled marketing campaign, export email delivery report from last week through natural language commands. This guide will help you understand how to give your Claude Agent SDK agent real control over a Enginemailer account through Composio's Enginemailer MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved.

Enginemailer logoEnginemailer
Api Key

Enginemailer is an email marketing platform for managing contacts, campaigns, and sending personalized emails. It helps businesses automate outreach and boost engagement with targeted messaging.

38 Tools

Introduction

This guide walks you through connecting Enginemailer to the Claude Agent SDK using the Composio tool router. By the end, you'll have a working Enginemailer agent that can add new subscriber to newsletter list, pause tomorrow's scheduled marketing campaign, export email delivery report from last week through natural language commands.

This guide will help you understand how to give your Claude Agent SDK agent real control over a Enginemailer account through Composio's Enginemailer MCP server.

Before we dive in, let's take a quick look at the key ideas and tools involved.

Also integrate Enginemailer with

TL;DR

Here's what you'll learn:
  • Get and set up your Claude/Anthropic and Composio API keys
  • Install the necessary dependencies
  • Initialize Composio and create a Tool Router session for Enginemailer
  • Configure an AI agent that can use Enginemailer as a tool
  • Run a live chat session where you can ask the agent to perform Enginemailer operations

What is Claude Agent SDK?

The Claude Agent SDK is Anthropic's official framework for building AI agents powered by Claude. It provides a streamlined interface for creating agents with MCP tool support and conversation management.

Key features include:

  • Native MCP Support: Built-in support for Model Context Protocol servers
  • Permission Modes: Control tool execution permissions
  • Streaming Responses: Real-time response streaming for interactive applications
  • Context Manager: Clean async context management for sessions

What is the Enginemailer MCP server, and what's possible with it?

The Enginemailer MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Enginemailer account. It provides structured and secure access to your email marketing platform, so your agent can perform actions like creating campaigns, managing subscriber lists, exporting reports, and sending personalized email campaigns on your behalf.

  • Campaign creation and scheduling: Direct your agent to set up new email campaigns, configure content, and schedule delivery to your audience.
  • Subscriber management: Have your agent add new subscribers to your lists, including custom fields and segmentation for targeted outreach.
  • Instant campaign delivery and controls: Command your agent to send campaigns immediately or pause scheduled campaigns for last-minute adjustments.
  • Campaign monitoring and reporting: Let your agent export detailed email campaign reports as CSV files and check the status of ongoing exports.
  • Audience segmentation and subcategory retrieval: Guide your agent to fetch subcategories and organize recipients for more personalized and effective campaigns.

What is the Composio tool router, and how does it fit here?

What is Composio SDK?

Composio's Composio SDK helps agents find the right tools for a task at runtime. You can plug in multiple toolkits (like Gmail, HubSpot, and GitHub), and the agent will identify the relevant app and action to complete multi-step workflows. This can reduce token usage and improve the reliability of tool calls. Read more here: Getting started with Composio SDK

The tool router generates a secure MCP URL that your agents can access to perform actions.

How the Composio SDK works

The Composio SDK follows a three-phase workflow:

  1. Discovery: Searches for tools matching your task and returns relevant toolkits with their details.
  2. Authentication: Checks for active connections. If missing, creates an auth config and returns a connection URL via Auth Link.
  3. Execution: Executes the action using the authenticated connection.

Step-by-step Guide

Step by step09 STEPS
1

Prerequisites

Before starting, make sure you have:
  • Composio API Key and Claude/Anthropic API Key
  • Primary know-how of Claude Agents SDK
  • A Enginemailer account
  • Some knowledge of Python
2

Getting API Keys for Claude/Anthropic and Composio

Claude/Anthropic API Key
  • Go to the Anthropic Console and create an API key. You'll need credits to use the models.
  • Keep the API key safe.
Composio API Key
  • Log in to the Composio dashboard.
  • Navigate to your API settings and generate a new API key.
  • Store this key securely as you'll need it for authentication.
3

Install dependencies

npm install @anthropic-ai/claude-agent-sdk @composio/core dotenv

Install the Composio SDK and the Claude Agents SDK.

What's happening:

  • @composio/core provides Composio integration for Anthropic
  • @anthropic-ai/claude-agent-sdk is the core agent framework
  • dotenv/config loads environment variables
4

Set up environment variables

bash
COMPOSIO_API_KEY=your_composio_api_key_here
USER_ID=your_user_id_here
ANTHROPIC_API_KEY=your_anthropic_api_key_here

Create a .env file in your project root.

What's happening:

  • COMPOSIO_API_KEY authenticates with Composio
  • USER_ID identifies the user for session management
  • ANTHROPIC_API_KEY authenticates with Anthropic/Claude
5

Import dependencies

import 'dotenv/config';
import readline from 'node:readline';
import { Composio } from '@composio/core';
import { query, type Options } from "@anthropic-ai/claude-agent-sdk";

dotenv.config();
What's happening:
  • We're importing all necessary libraries including the Claude Agent SDK and Composio
  • The dotenv.config() function loads environment variables from your .env file
  • This setup prepares the foundation for connecting Claude with Enginemailer functionality
6

Create a Composio instance and Tool Router session

async function chat() {
  const { COMPOSIO_API_KEY, USER_ID } = process.env;
  if (!COMPOSIO_API_KEY || !USER_ID) {
    throw new Error('COMPOSIO_API_KEY and USER_ID required in .env');
  }

  const composio = new Composio({ apiKey: COMPOSIO_API_KEY });

  // Create Tool Router session for Enginemailer
  const session = await composio.create(USER_ID, {
    toolkits: ['enginemailer'],
  });
  const mcpUrl = session?.mcp.url;
What's happening:
  • The function checks for the required COMPOSIO_API_KEY environment variable
  • We're creating a Composio instance using our API key
  • The create method creates a Tool Router session for Enginemailer
  • The returned url is the MCP server URL that your agent will use
7

Configure Claude Agent with MCP

const options: Options = {
  permissionMode: 'bypassPermissions',
  mcpServers: {
    composio: {
      type: 'http',
      url: mcpUrl,
      headers: { 'x-api-key': COMPOSIO_API_KEY }
    }
  },
  systemPrompt: 'You are a helpful assistant with access to Enginemailer tools via Composio.',
  maxTurns: 10,
};
What's happening:
  • We're configuring the Claude Agent options with the MCP server URL
  • permissionMode: 'bypassPermissions' allows the agent to execute operations without asking for permission each time
  • The system prompt instructs the agent that it has access to Enginemailer
  • maxTurns: 10 limits the conversation length to prevent excessive API usage
8

Create client and start chat loop

const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
    prompt: 'You: '
  });

  console.log('\nChat started. Type "exit" to quit.\n');

  let isProcessing = false;

  async function ask(prompt: string) {
    isProcessing = true;
    rl.pause();

    process.stdout.write('Claude is thinking...');
    const stream = query({ prompt, options });

    let firstChunk = true;
    for await (const msg of stream) {
      const content = (msg as any).message?.content || (msg as any).content;
      if (Array.isArray(content)) {
        for (const block of content) {
          if (block.type === 'text' && block.text) {
            if (firstChunk) {
              process.stdout.write('\r\x1b[K');
              process.stdout.write('Claude: ');
              firstChunk = false;
            }
            process.stdout.write(block.text);
          }
        }
      }
    }
    process.stdout.write('\n\n');

    isProcessing = false;
    rl.resume();
    rl.prompt();
  }

  rl.on('line', async (line) => {
    if (isProcessing) return;

    const input = line.trim();
    if (input === 'exit') {
      rl.close();
      process.exit(0);
    }
    if (input) await ask(input);
    else rl.prompt();
  });

  await ask('What can you help me with?');
}
What's happening:
  • The readline interface is created to handle user input and output
  • The query function is used to send the user's input to the agent
  • The chat loop continues until the user types 'exit' or 'quit'
9

Run the application

try {
  await chat();
} catch (error) {
  console.error(error);
  process.exit(1);
}
What's happening:
  • The chat function is the entry point for the application
  • The try-catch block is used to handle any errors that occur

Complete Code

Here's the complete code to get you started with Enginemailer and Claude Agent SDK:

import 'dotenv/config';
import readline from 'node:readline';
import { Composio } from '@composio/core';
import { query, type Options } from "@anthropic-ai/claude-agent-sdk";

async function chat() {
  const { COMPOSIO_API_KEY, USER_ID } = process.env;
  if (!COMPOSIO_API_KEY || !USER_ID) {
    throw new Error('COMPOSIO_API_KEY and USER_ID required in .env');
  }

  const composio = new Composio({ apiKey: COMPOSIO_API_KEY });
  const session = await composio.create(USER_ID, {
    toolkits: ['enginemailer']
  });
  const mcp_url = session?.mcp.url;

  const options: Options = {
    permissionMode: 'bypassPermissions',
    mcpServers: {
      composio: {
        type: 'http',
        url: mcp_url,
        headers: { 'x-api-key': COMPOSIO_API_KEY }
      }
    },
    systemPrompt: 'You are a helpful assistant with access to Enginemailer tools via Composio.',
    maxTurns: 10,
  };

  const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
    prompt: 'You: '
  });

  console.log('\nChat started. Type "exit" to quit.\n');

  let isProcessing = false;

  async function ask(prompt: string) {
    isProcessing = true;
    rl.pause();

    process.stdout.write('Claude is thinking...');
    const stream = query({ prompt, options });

    let firstChunk = true;
    for await (const msg of stream) {
      const content = (msg as any).message?.content || (msg as any).content;
      if (Array.isArray(content)) {
        for (const block of content) {
          if (block.type === 'text' && block.text) {
            if (firstChunk) {
              process.stdout.write('\r\x1b[K');
              process.stdout.write('Claude: ');
              firstChunk = false;
            }
            process.stdout.write(block.text);
          }
        }
      }
    }
    process.stdout.write('\n\n');

    isProcessing = false;
    rl.resume();
    rl.prompt();
  }

  rl.on('line', async (line) => {
    if (isProcessing) return;

    const input = line.trim();
    if (input === 'exit') {
      rl.close();
      process.exit(0);
    }
    if (input) await ask(input);
    else rl.prompt();
  });

  await ask('What can you help me with?');
}

try {
  await chat();
} catch (error) {
  console.error(error);
  process.exit(1);
}

Conclusion

You've successfully built a Claude Agent SDK agent that can interact with Enginemailer through Composio's Tool Router.

Key features:

  • Native MCP support through Claude's agent framework
  • Streaming responses for real-time interaction
  • Permission bypass for smooth automated workflows
You can extend this by adding more toolkits, implementing custom business logic, or building a web interface around the agent.
TOOLS

Supported Tools

Every Enginemailer action and event your agent gets out of the box.

Activate Subscriber

Tool to activate an inactive subscriber in EngineMailer.

Add or Update Subscriber

Tool to add or update a subscriber with custom fields via N8N integration.

Check Batch Update Status

Tool to check the status of a batch subscriber update operation.

Batch Update Subscribers

Tool to add or update multiple subscribers with custom fields in a single batch operation.

Check Export Status V2

Tool to check status of a previously requested CSV report export.

Test API Connection

Tool to test API connection and verify authentication.

Create Campaign

Tool to create a new email campaign.

Delete Campaign

Tool to delete an undelivered email campaign.

Delete Recipient List

Tool to delete an existing recipient list from a targeted campaign.

Delete Subscriber

Tool to remove a subscriber from the system by email address.

Export CSV Report V2

Tool to export a transactional email report as CSV.

Find Subscriber

Tool to find a subscriber by email address via N8N integration.

Get Custom Field List

Tool to retrieve the list of custom fields configured for subscribers.

Get List Campaign

Tool to get a list of undelivered campaigns.

Get New Subscribers

Tool to retrieve new subscribers with optional filtering by source, form, page, or popup.

Get Subcategories

Tool to retrieve subcategories for a given category.

Get Subscriber

Tool to retrieve subscriber information by email address.

Get Subscriber Autoresponder Completed

Tool to retrieve subscribers who completed autoresponders with optional filtering by autoresponder ID.

Get Subscriber Autoresponder Triggered

Tool to retrieve subscribers who triggered autoresponders with optional filtering by autoresponder ID.

Get Deleted Subscribers

Tool to retrieve deleted subscribers since last polling date.

Get Subscribers Modified

Tool to retrieve modified subscribers since last polling date with optional limit.

Get Subscribers Tagged

Tool to retrieve subscribers who were tagged with optional filtering by subcategory.

Get Untagged Subscribers

Tool to retrieve subscribers who were untagged from subcategories.

Get Unsubscribe Events

Tool to retrieve unsubscribe events with optional filtering by campaign or autoresponder.

Insert Subscriber

Tool to add a new subscriber with optional custom fields.

List Autoresponders

Tool to retrieve a list of all autoresponders.

List Campaigns

Tool to retrieve a list of all campaigns.

List Forms

Tool to retrieve a list of available forms in Enginemailer.

List Pages

Tool to retrieve a list of all pages.

List Popups

Tool to retrieve a list of popups from Enginemailer.

List Templates

Tool to retrieve a list of all email templates.

Pause Campaign

Tool to pause a scheduled email campaign.

Create/Update Category

Tool to create or update a category for subscriber segmentation.

Update Subscriber

Tool to update data for an existing subscriber in EngineMailer.

Send Campaign

Tool to send an email campaign immediately.

Tag Subscriber to Subcategory

Tool to tag a subscriber to a specific subcategory via N8N API endpoint.

Unsubscribe (N8N)

Tool to unsubscribe a subscriber via N8N API endpoint.

Unsubscribe Subscriber

Tool to unsubscribe a subscriber from the email list.

FAQ

Frequently asked questions

With a standalone Enginemailer MCP server, the agents and LLMs can only access a fixed set of Enginemailer tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Enginemailer and many other apps based on the task at hand, all through a single MCP endpoint.

Yes, you can. Claude Agent SDK fully supports MCP integration. You get structured tool calling, message history handling, and model orchestration while Tool Router takes care of discovering and serving the right Enginemailer tools.

Yes, absolutely. You can configure which Enginemailer scopes and actions are allowed when connecting your account to Composio. You can also bring your own OAuth credentials or API configuration so you keep full control over what the agent can do.

All sensitive data such as tokens, keys, and configuration is fully encrypted at rest and in transit. Composio is SOC 2 Type 2 compliant and follows strict security practices so your Enginemailer data and credentials are handled as safely as possible.

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