How to integrate Enginemailer MCP with OpenAI Agents SDK

This guide walks you through connecting Enginemailer to the OpenAI Agents 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 OpenAI Agents 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 OpenAI Agents 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 OpenAI Agents 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 OpenAI 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 OpenAI Agents SDK?

The OpenAI Agents SDK is a lightweight framework for building AI agents that can use tools and maintain conversation state. It provides a simple interface for creating agents with hosted MCP tool support.

Key features include:

  • Hosted MCP Tools: Connect to external services through hosted MCP endpoints
  • SQLite Sessions: Persist conversation history across interactions
  • Simple API: Clean interface with Agent, Runner, and tool configuration
  • Streaming Support: Real-time response streaming for interactive applications

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 OpenAI API Key
  • Primary know-how of OpenAI Agents SDK
  • A live Enginemailer project
  • Some knowledge of Python or Typescript
2

Getting API Keys for OpenAI and Composio

OpenAI API Key
  • Go to the OpenAI dashboard and create an API key. You'll need credits to use the models, or you can connect to another model provider.
  • Keep the API key safe.
Composio API Key
3

Install dependencies

npm install @composio/openai-agents @openai/agents dotenv

Install the Composio SDK and the OpenAI Agents SDK.

4

Set up environment variables

bash
OPENAI_API_KEY=sk-...your-api-key
COMPOSIO_API_KEY=your-api-key
USER_ID=composio_user@gmail.com

Create a .env file and add your OpenAI and Composio API keys.

5

Import dependencies

import 'dotenv/config';
import { Composio } from '@composio/core';
import { OpenAIAgentsProvider } from '@composio/openai-agents';
import { Agent, hostedMcpTool, run, OpenAIConversationsSession } from '@openai/agents';
import * as readline from 'readline';
What's happening:
  • You're importing all necessary libraries.
  • The Composio and OpenAIAgentsProvider classes are imported to connect your OpenAI agent to Composio tools like Enginemailer.
6

Set up the Composio instance

dotenv.config();

const composioApiKey = process.env.COMPOSIO_API_KEY;
const userId = process.env.USER_ID;

if (!composioApiKey) {
  throw new Error('COMPOSIO_API_KEY is not set. Create a .env file with COMPOSIO_API_KEY=your_key');
}
if (!userId) {
  throw new Error('USER_ID is not set');
}

// Initialize Composio
const composio = new Composio({
  apiKey: composioApiKey,
  provider: new OpenAIAgentsProvider(),
});
What's happening:
  • dotenv.config() loads your .env file so COMPOSIO_API_KEY and USER_ID are available as environment variables.
  • Creating a Composio instance using the API Key and OpenAIAgentsProvider class.
7

Create a Tool Router session

// Create Tool Router session for Enginemailer
const session = await composio.create(userId as string, {
  toolkits: ['enginemailer'],
});
const mcpUrl = session.mcp.url;

What is happening:

  • You give the Tool Router the user id and the toolkits you want available. Here, it is only enginemailer.
  • The router checks the user's Enginemailer connection and prepares the MCP endpoint.
  • The returned session.mcp.url is the MCP URL that your agent will use to access Enginemailer.
  • This approach keeps things lightweight and lets the agent request Enginemailer tools only when needed during the conversation.
8

Configure the agent

// Configure agent with MCP tool
const agent = new Agent({
  name: 'Assistant',
  model: 'gpt-5',
  instructions:
    'You are a helpful assistant that can access Enginemailer. Help users perform Enginemailer operations through natural language.',
  tools: [
    hostedMcpTool({
      serverLabel: 'tool_router',
      serverUrl: mcpUrl,
      headers: { 'x-api-key': composioApiKey },
      requireApproval: 'never',
    }),
  ],
});
What's happening:
  • We're creating an Agent instance with a name, model (gpt-5), and clear instructions about its purpose.
  • The agent's instructions tell it that it can access Enginemailer and help with queries, inserts, updates, authentication, and fetching database information.
  • The tools array includes a hostedMcpTool that connects to the MCP server URL we created earlier.
  • The headers object includes the Composio API key for secure authentication with the MCP server.
  • requireApproval: 'never' means the agent can execute Enginemailer operations without asking for permission each time, making interactions smoother.
9

Start chat loop and handle conversation

// Keep conversation state across turns
const conversationSession = new OpenAIConversationsSession();

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

console.log('\nComposio Tool Router session created.');
console.log('\nChat started. Type your requests below.');
console.log("Commands: 'exit', 'quit', or 'q' to end\n");

try {
  const first = await run(agent, 'What can you help me with?', { session: conversationSession });
  console.log(`Assistant: ${first.finalOutput}\n`);
} catch (e) {
  console.error('Error:', e instanceof Error ? e.message : e, '\n');
}

rl.prompt();

rl.on('line', async (userInput) => {
  const text = userInput.trim();

  if (['exit', 'quit', 'q'].includes(text.toLowerCase())) {
    console.log('Goodbye!');
    rl.close();
    process.exit(0);
  }

  if (!text) {
    rl.prompt();
    return;
  }

  try {
    const result = await run(agent, text, { session: conversationSession });
    console.log(`\nAssistant: ${result.finalOutput}\n`);
  } catch (e) {
    console.error('Error:', e instanceof Error ? e.message : e, '\n');
  }

  rl.prompt();
});

rl.on('close', () => {
  console.log('\n👋 Session ended.');
  process.exit(0);
});
What's happening:
  • The program prints a session URL that you visit to authorize Enginemailer.
  • After authorization, the chat begins.
  • Each message you type is processed by the agent using run().
  • The responses are printed to the console.
  • Typing exit, quit, or q cleanly ends the chat.

Complete Code

Here's the complete code to get you started with Enginemailer and OpenAI Agents SDK:

import 'dotenv/config';
import { Composio } from '@composio/core';
import { OpenAIAgentsProvider } from '@composio/openai-agents';
import { Agent, hostedMcpTool, run, OpenAIConversationsSession } from '@openai/agents';
import * as readline from 'readline';

const composioApiKey = process.env.COMPOSIO_API_KEY;
const userId = process.env.USER_ID;

if (!composioApiKey) {
  throw new Error('COMPOSIO_API_KEY is not set. Create a .env file with COMPOSIO_API_KEY=your_key');
}
if (!userId) {
  throw new Error('USER_ID is not set');
}

// Initialize Composio
const composio = new Composio({
  apiKey: composioApiKey,
  provider: new OpenAIAgentsProvider(),
});

async function main() {
  // Create Tool Router session
  const session = await composio.create(userId as string, {
    toolkits: ['enginemailer'],
  });
  const mcpUrl = session.mcp.url;

  // Configure agent with MCP tool
  const agent = new Agent({
    name: 'Assistant',
    model: 'gpt-5',
    instructions:
      'You are a helpful assistant that can access Enginemailer. Help users perform Enginemailer operations through natural language.',
    tools: [
      hostedMcpTool({
        serverLabel: 'tool_router',
        serverUrl: mcpUrl,
        headers: { 'x-api-key': composioApiKey },
        requireApproval: 'never',
      }),
    ],
  });

  // Keep conversation state across turns
  const conversationSession = new OpenAIConversationsSession();

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

  console.log('\nComposio Tool Router session created.');
  console.log('\nChat started. Type your requests below.');
  console.log("Commands: 'exit', 'quit', or 'q' to end\n");

  try {
    const first = await run(agent, 'What can you help me with?', { session: conversationSession });
    console.log(`Assistant: ${first.finalOutput}\n`);
  } catch (e) {
    console.error('Error:', e instanceof Error ? e.message : e, '\n');
  }

  rl.prompt();

  rl.on('line', async (userInput) => {
    const text = userInput.trim();

    if (['exit', 'quit', 'q'].includes(text.toLowerCase())) {
      console.log('Goodbye!');
      rl.close();
      process.exit(0);
    }

    if (!text) {
      rl.prompt();
      return;
    }

    try {
      const result = await run(agent, text, { session: conversationSession });
      console.log(`\nAssistant: ${result.finalOutput}\n`);
    } catch (e) {
      console.error('Error:', e instanceof Error ? e.message : e, '\n');
    }

    rl.prompt();
  });

  rl.on('close', () => {
    console.log('\nSession ended.');
    process.exit(0);
  });
}

main().catch((err) => {
  console.error('Fatal error:', err);
  process.exit(1);
});

Conclusion

This was a starter code for integrating Enginemailer MCP with OpenAI Agents SDK to build a functional AI agent that can interact with Enginemailer.

Key features:

  • Hosted MCP tool integration through Composio's Tool Router
  • SQLite session persistence for conversation history
  • Simple async chat loop for interactive testing
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. OpenAI Agents 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.

Start with Enginemailer.It takes 30 seconds.

Managed auth, hosted MCP servers, and every Enginemailer tool your agent needs.Free to start.

Start building