How to integrate Emelia MCP with LangChain

This guide walks you through connecting Emelia to LangChain using the Composio tool router. By the end, you'll have a working Emelia agent that can find email address for john doe at acme corp, add jane.smith@email.com to new leads campaign, remove bob.jones@company.com from q2 outreach campaign through natural language commands. This guide will help you understand how to give your LangChain agent real control over a Emelia account through Composio's Emelia MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved.

Emelia logoEmelia
Api Key

Emelia is an all-in-one B2B prospecting platform for cold-email, LinkedIn outreach, and prospect research. It streamlines outbound campaigns so you can find, engage, and warm up leads faster.

22 Tools

Introduction

This guide walks you through connecting Emelia to LangChain using the Composio tool router. By the end, you'll have a working Emelia agent that can find email address for john doe at acme corp, add jane.smith@email.com to new leads campaign, remove bob.jones@company.com from q2 outreach campaign through natural language commands.

This guide will help you understand how to give your LangChain agent real control over a Emelia account through Composio's Emelia MCP server.

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

Also integrate Emelia with

TL;DR

Here's what you'll learn:
  • Get and set up your OpenAI and Composio API keys
  • Connect your Emelia project to Composio
  • Create a Tool Router MCP session for Emelia
  • Initialize an MCP client and retrieve Emelia tools
  • Build a LangChain agent that can interact with Emelia
  • Set up an interactive chat interface for testing

What is LangChain?

LangChain is a framework for developing applications powered by language models. It provides tools and abstractions for building agents that can reason, use tools, and maintain conversation context.

Key features include:

  • Agent Framework: Build agents that can use tools and make decisions
  • MCP Integration: Connect to external services through Model Context Protocol adapters
  • Memory Management: Maintain conversation history across interactions
  • Multi-Provider Support: Works with OpenAI, Anthropic, and other LLM providers

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

The Emelia MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Emelia account. It provides structured and secure access to your B2B outreach operations, so your agent can perform actions like launching campaigns, managing contacts, finding prospect emails, and tracking outreach activities on your behalf.

  • Automated campaign creation and management: Instruct your agent to create new email or LinkedIn campaigns, add contacts, or remove contacts from campaigns to keep your outreach efforts streamlined and organized.
  • Prospect email discovery: Have your agent find verified email addresses for specific contacts using full name and company details, accelerating your lead generation process.
  • Contact blacklisting and compliance: Direct your agent to add contacts to the blacklist, ensuring that no further emails are sent and helping you stay compliant with outreach best practices.
  • Real-time campaign activity tracking: Retrieve detailed campaign activities and create webhooks to monitor engagement, so you’re always up to date on your outreach performance.
  • Webhook automation for event-driven workflows: Let your agent create or delete webhooks to automate follow-ups and synchronize campaign updates across your sales stack.

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 step10 STEPS
1

Prerequisites

Before starting this tutorial, make sure you have:
  • Python 3.10 or higher installed on your system
  • A Composio account with an API key
  • An OpenAI API key
  • Basic familiarity with Python and async programming
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
  • 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 @composio/langchain @langchain/core @langchain/openai @langchain/mcp-adapters dotenv

Install the required packages for LangChain with MCP support.

What's happening:

  • @composio/langchain provides Composio integration for LangChain
  • @langchain/mcp-adapters enables MCP client connections
  • @langchain/core is the core agent framework
  • dotenv/config loads environment variables
4

Set up environment variables

bash
COMPOSIO_API_KEY=your_composio_api_key_here
COMPOSIO_USER_ID=your_composio_user_id_here
OPENAI_API_KEY=your_openai_api_key_here

Create a .env file in your project root.

What's happening:

  • COMPOSIO_API_KEY authenticates your requests to Composio's API
  • COMPOSIO_USER_ID identifies the user for session management
  • OPENAI_API_KEY enables access to OpenAI's language models
5

Import dependencies

import { Composio } from '@composio/core';
import { LangchainProvider } from '@composio/langchain';
import { MultiServerMCPClient } from "@langchain/mcp-adapters";
import { createAgent } from "langchain";
import * as readline from 'readline';
import 'dotenv/config';

dotenv.config();
What's happening:
  • We're importing LangChain's MCP adapter and Composio SDK
  • The dotenv/config import loads environment variables from your .env file
  • This setup prepares the foundation for connecting LangChain with Emelia functionality through MCP
6

Initialize Composio client

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

if (!composioApiKey) throw new Error('COMPOSIO_API_KEY is not set');
if (!userId) throw new Error('COMPOSIO_USER_ID is not set');

async function main() {
    const composio = new Composio({
        apiKey: composioApiKey as string,
        provider: new LangchainProvider()
    });
What's happening:
  • We're loading the COMPOSIO_API_KEY from environment variables and validating it exists
  • Creating a Composio instance that will manage our connection to Emelia tools
  • Validating that COMPOSIO_USER_ID is also set before proceeding
7

Create a Tool Router session

const session = await composio.create(
    userId as string,
    {
        toolkits: ['emelia']
    }
);

const url = session.mcp.url;
What's happening:
  • We're creating a Tool Router session that gives your agent access to Emelia tools
  • The create method takes the user ID and specifies which toolkits should be available
  • The returned session.mcp.url is the MCP server URL that your agent will use
  • This approach allows the agent to dynamically load and use Emelia tools as needed
8

Configure the agent with the MCP URL

const client = new MultiServerMCPClient({
    "emelia-agent": {
        transport: "http",
        url: url,
        headers: {
            "x-api-key": process.env.COMPOSIO_API_KEY
        }
    }
});

const tools = await client.getTools();

const agent = createAgent({ model: "gpt-5", tools });
What's happening:
  • We're creating a MultiServerMCPClient that connects to our Emelia MCP server via HTTP
  • The client is configured with a name and the URL from our Tool Router session
  • getTools() retrieves all available Emelia tools that the agent can use
  • We're creating a LangChain agent using the GPT-5 model
9

Set up interactive chat interface

let conversationHistory: any[] = [];

console.log("Chat started! Type 'exit' or 'quit' to end the conversation.\n");
console.log("Ask any Emelia related question or task to the agent.\n");

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

rl.prompt();

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

    if (['exit', 'quit', 'bye'].includes(trimmedInput.toLowerCase())) {
        console.log("\nGoodbye!");
        rl.close();
        process.exit(0);
    }

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

    conversationHistory.push({ role: "user", content: trimmedInput });
    console.log("\nAgent is thinking...\n");

    const response = await agent.invoke({ messages: conversationHistory });
    conversationHistory = response.messages;

    const finalResponse = response.messages[response.messages.length - 1]?.content;
    console.log(`Agent: ${finalResponse}\n`);
        
        rl.prompt();
    });

    rl.on('close', () => {
        console.log('\n👋 Session ended.');
        process.exit(0);
    });
What's happening:
  • We initialize an empty conversationHistory list to maintain context across interactions
  • A readline interface is used to continuously accept user input from the command line
  • When a user types a message, it's added to the conversation history and sent to the agent
  • The agent processes the request using the invoke() method with the full conversation history
  • Users can type 'exit', 'quit', or 'bye' to end the chat session gracefully
10

Run the application

main().catch((err) => {
    console.error('Fatal error:', err);
    process.exit(1);
});
What's happening:
  • We call the main() function to start the application

Complete Code

Here's the complete code to get you started with Emelia and LangChain:

import { Composio } from '@composio/core';
import { LangchainProvider } from '@composio/langchain';
import { MultiServerMCPClient } from "@langchain/mcp-adapters";  
import { createAgent } from "langchain";
import * as readline from 'readline';
import 'dotenv/config';

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

if (!composioApiKey) throw new Error('COMPOSIO_API_KEY is not set');
if (!userId) throw new Error('COMPOSIO_USER_ID is not set');

async function main() {
    const composio = new Composio({
        apiKey: composioApiKey as string,
        provider: new LangchainProvider()
    });

    const session = await composio.create(
        userId as string,
        {
            toolkits: ['emelia']
        }
    );

    const url = session.mcp.url;
    
    const client = new MultiServerMCPClient({
        "emelia-agent": {
            transport: "http",
            url: url,
            headers: {
                "x-api-key": process.env.COMPOSIO_API_KEY
            }
        }
    });
    
    const tools = await client.getTools();
  
    const agent = createAgent({ model: "gpt-5", tools });
    
    let conversationHistory: any[] = [];
    
    console.log("Chat started! Type 'exit' or 'quit' to end the conversation.\n");
    console.log("Ask any Emelia related question or task to the agent.\n");
    
    const rl = readline.createInterface({
        input: process.stdin,
        output: process.stdout,
        prompt: 'You: '
    });

    rl.prompt();

    rl.on('line', async (userInput: string) => {
        const trimmedInput = userInput.trim();
        
        if (['exit', 'quit', 'bye'].includes(trimmedInput.toLowerCase())) {
            console.log("\nGoodbye!");
            rl.close();
            process.exit(0);
        }
        
        if (!trimmedInput) {
            rl.prompt();
            return;
        }
        
        conversationHistory.push({ role: "user", content: trimmedInput });
        console.log("\nAgent is thinking...\n");
        
        const response = await agent.invoke({ messages: conversationHistory });
        conversationHistory = response.messages;
        
        const finalResponse = response.messages[response.messages.length - 1]?.content;
        console.log(`Agent: ${finalResponse}\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

You've successfully built a LangChain agent that can interact with Emelia through Composio's Tool Router.

Key features of this implementation:

  • Dynamic tool loading through Composio's Tool Router
  • Conversation history maintenance for context-aware responses
  • Async Python provides clean, efficient execution of agent workflows
You can extend this further by adding error handling, implementing specific business logic, or integrating additional Composio toolkits to create multi-app workflows.
TOOLS

Supported Tools

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

Add Contact to Blacklist

Tool to add a contact to the email blacklist.

Add Contact To Campaign

Tool to add a contact to an email campaign.

Create Campaign

Tool to create a new email campaign.

Create LinkedIn Campaign

Tool to create a new LinkedIn campaign.

Create Webhook

Tool to create a new webhook for campaign events.

Delete Contact From Campaign

Tool to remove a contact from an email campaign.

Delete Contact From LinkedIn Campaign

Tool to delete a contact from a LinkedIn campaign.

Delete Webhook

Tool to delete a specific webhook.

Find Email of Single Contact

Tool to initiate a job to find the email address of a specific contact.

Get Campaign Activities

Tool to retrieve activities for a specific email campaign.

Get Find Email Result

Tool to retrieve the result of a previously initiated email find job.

Get Find Phone Result

Tool to retrieve the outcome of a previously initiated phone-find job.

Get Campaign Activities

Tool to retrieve activities for a campaign.

Get Verify Email Result

Tool to get the result of an email verification job.

Initiate Email Verification Job

Tool to initiate an asynchronous email verification job.

Initiate Phone Find Job

Tool to initiate a phone-find job for a single contact.

List Campaign Contacts

Tool to list contacts in a specific email campaign.

List Campaigns

Tool to retrieve all email campaigns.

List Email Providers

Tool to retrieve all configured email providers.

List LinkedIn Campaigns

Tool to list all LinkedIn campaigns.

List webhooks

Tool to retrieve all webhooks.

Remove Contact from Blacklist

Tool to remove a contact or domain from the email blacklist.

FAQ

Frequently asked questions

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

Yes, you can. LangChain 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 Emelia tools.

Yes, absolutely. You can configure which Emelia 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 Emelia data and credentials are handled as safely as possible.

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