How to integrate Etermin MCP with LangChain

This guide walks you through connecting Etermin to LangChain using the Composio tool router. By the end, you'll have a working Etermin agent that can add new client contact for booking, remove canceled appointment from calendar, create voucher for returning customer through natural language commands. This guide will help you understand how to give your LangChain agent real control over a Etermin account through Composio's Etermin MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved.

Etermin logoEtermin
Api Key

eTermin is an online appointment scheduling platform for businesses to manage bookings. It streamlines client appointments, saving time and reducing scheduling conflicts.

78 Tools

Introduction

This guide walks you through connecting Etermin to LangChain using the Composio tool router. By the end, you'll have a working Etermin agent that can add new client contact for booking, remove canceled appointment from calendar, create voucher for returning customer through natural language commands.

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

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

Also integrate Etermin with

TL;DR

Here's what you'll learn:
  • Get and set up your OpenAI and Composio API keys
  • Connect your Etermin project to Composio
  • Create a Tool Router MCP session for Etermin
  • Initialize an MCP client and retrieve Etermin tools
  • Build a LangChain agent that can interact with Etermin
  • 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 Etermin MCP server, and what's possible with it?

The Etermin MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Etermin account. It provides structured and secure access to your appointment scheduling system, so your agent can perform actions like creating contacts, managing bookings, updating resources, and handling calendar events on your behalf.

  • Automated contact and user creation: Instantly add new clients or team members to your Etermin account, streamlining onboarding and customer management.
  • Effortless appointment and calendar management: Let your agent delete existing appointments or calendars, freeing up schedules and reducing manual work.
  • Resource and service administration: Automatically create or remove resources and services, ensuring your booking system stays current as your business evolves.
  • Voucher and webhook setup: Quickly generate new vouchers for promotions or set up webhooks for real-time event notifications and integrations.
  • Contact and service deletion: Easily remove outdated contacts or services, keeping your scheduling platform organized and clutter-free.

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 Etermin 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 Etermin 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: ['etermin']
    }
);

const url = session.mcp.url;
What's happening:
  • We're creating a Tool Router session that gives your agent access to Etermin 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 Etermin tools as needed
8

Configure the agent with the MCP URL

const client = new MultiServerMCPClient({
    "etermin-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 Etermin MCP server via HTTP
  • The client is configured with a name and the URL from our Tool Router session
  • getTools() retrieves all available Etermin 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 Etermin 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 Etermin 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: ['etermin']
        }
    );

    const url = session.mcp.url;
    
    const client = new MultiServerMCPClient({
        "etermin-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 Etermin 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 Etermin 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 Etermin action and event your agent gets out of the box.

Assign Calendar Service

Tool to assign a service to a calendar in eTermin.

Create Absence

Tool to create an absence (non-working time) for a specific calendar.

Create Anchortime

Tool to create anchortimes (recurring time slots) in a calendar.

Create Anchortime by Date

Tool to create anchortimes by date.

Create Appointment

Tool to create a new appointment in eTermin.

Create Appointment via Sync

Tool to create an appointment via sync in eTermin.

Create Calendar Return Time

Tool to create a return time for a calendar.

Create Contact

Tool to create a new contact in eTermin.

Create Service

Tool to create a new service in eTermin.

Create Service Group

Tool to create a new service group in eTermin.

Create User

Tool to create a new user.

Create Usermapping

Tool to create a new usermapping in eTermin.

Create Voucher

Creates a new discount voucher in eTermin.

Create Webhook

Creates a webhook (web push notification) in eTermin to receive real-time updates about appointments.

Create Working Time

Tool to create a new working time slot in eTermin.

Create Working Times Date

Tool to create a working times date slot for a calendar.

Delete Absence

Tool to delete an absence (non-working time) from a calendar.

Delete Anchortime

Delete an anchortime from eTermin by its ID.

Delete Anchortime By Date

Delete an anchortime by date using its ID.

Delete Appointment

Delete an existing appointment by its ID.

Delete Appointment via Sync

Tool to delete appointments via the sync endpoint.

Delete Calendar

Delete a calendar from your eTermin account.

Delete Calendar Return Time

Delete a return time from a calendar.

Delete Calendar Service

Delete an assigned service from a calendar in eTermin.

Delete Contact

Delete a contact from your eTermin account by its contact ID.

Delete Resource

Delete an eTermin resource by type and ID.

Delete Service

Permanently deletes a service from your eTermin account by its ID.

Delete Service Group

Delete a service group from your eTermin account by its ID.

Delete User

Deletes an existing user from the eTermin account.

Delete Usermapping

Delete a usermapping by its ID.

Delete Voucher

Permanently deletes a voucher from eTermin by its voucher code.

Delete Webhook

Delete an existing webhook by its unique identifier.

Delete Working Times

Tool to delete working times from a calendar.

Delete Working Times Date

Tool to delete working times date entries from eTermin.

Get Absences

Tool to retrieve absences (non-working times) for a specific calendar.

Get Anchortime by Date

Tool to retrieve anchortimes by date.

Get Anchortimes

Tool to retrieve anchortime details.

Get Appointment Sync

Tool to synchronize appointments incrementally from eTermin.

Get Bookingpage Logs

Tool to retrieve bookingpage request logs from eTermin.

Get Calendar Return Time

Tool to retrieve return times for a specific calendar.

Get Calendars

Tool to retrieve calendars.

Get Calendar Service Assignments

Tool to retrieve calendar service assignments.

Get Company

Tool to retrieve company account details.

Get Contact By ID

Tool to retrieve a specific contact by ID, external ID, or email.

Get Contacts

Tool to retrieve a list of contacts.

Get Deleted Appointments

Tool to retrieve a list of deleted appointments from eTermin.

Get Message Logs

Tool to retrieve message logs from eTermin.

Get Customer Ratings

Tool to retrieve a list of customer ratings from eTermin.

Get Service By ID

Tool to retrieve a specific service from eTermin.

Get Service Calendar

Tool to retrieve calendars for a specific service ID.

Get Service Group

Tool to retrieve service group details from eTermin.

Get Services

Tool to retrieve a list of services.

Get Survey Results

Tool to retrieve survey results from eTermin.

Get Timeslots

Tool to retrieve available timeslots for a specific calendar on a given date.

Get Usermapping

Tool to retrieve usermapping information.

Get Users

Tool to retrieve a list of users.

Get Working Times

Tool to retrieve working times for a specific calendar.

Get Working Times Date

Tool to retrieve working times for a specific calendar on a specific date.

List Appointments

Tool to retrieve a filtered list of appointments from eTermin in a specified date range.

List Vouchers

Retrieve all vouchers (discount codes) from your eTermin account.

List Webhooks

Tool to retrieve webhooks.

Update Service via PUT

Tool to update a service in eTermin.

Update Absence

Tool to update an absence (non-working time) for a calendar in eTermin.

Update Anchortime

Update an existing anchortime in eTermin.

Update Anchortime By Date

Tool to update anchortimes by date in eTermin.

Update Appointment

Tool to update an existing appointment in eTermin.

Update Calendar

Update an existing calendar in eTermin.

Update Calendar Return Time

Tool to update a return time for a calendar in eTermin.

Update Contact

Tool to update an existing contact in eTermin.

Update Resource

Update an existing eTermin resource (contact, service, calendar, user, or voucher).

Update Service

Tool to update an existing service.

Update Service Group

Tool to update an existing service group in eTermin.

Update Synchronised Appointment

Tool to update a synchronised appointment in eTermin.

Update Usermapping

Update an existing usermapping in eTermin.

Update Voucher

Updates an existing voucher in eTermin.

Update Webhook

Update an existing webhook configuration in eTermin.

Update Working Times

Tool to update working times for a calendar in eTermin.

Update Working Times Date

Tool to update working times date for a calendar.

FAQ

Frequently asked questions

With a standalone Etermin MCP server, the agents and LLMs can only access a fixed set of Etermin tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Etermin 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 Etermin tools.

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

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