How to integrate Neutrino MCP with LangChain

This guide walks you through connecting Neutrino to LangChain using the Composio tool router. By the end, you'll have a working Neutrino agent that can detect profanity in user-submitted comments, convert 50 usd to eur instantly, geocode address to get latitude and longitude through natural language commands. This guide will help you understand how to give your LangChain agent real control over a Neutrino account through Composio's Neutrino MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved.

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Neutrino

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Neutrino is a powerful API suite for data validation, geolocation, and security tasks. It streamlines complex checks and enriches your applications with just a single API key.

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Introduction

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

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

Also integrate Neutrino with

OpenAI Agents SDK Claude Agent SDK Claude Code Claude Cowork Codex OpenClaw Hermes CLI Google ADK Vercel AI SDK Mastra AI LlamaIndex CrewAI

TL;DR

Here's what you'll learn:

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

The Neutrino MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Neutrino account. It provides structured and secure access to Neutrino’s robust suite of APIs, so your agent can validate data, analyze geolocations, assess security risks, convert currencies, and clean content automatically on your behalf.

Real-time data validation and analysis: Have your agent validate email addresses, check mobile numbers, and analyze BIN (bank identification numbers) for accuracy and reliability.
Geolocation and address intelligence: Ask your agent to geocode addresses to coordinates, or perform reverse geocoding to turn latitude and longitude into real-world locations for smarter workflows.
Content safety and cleaning: Let your agent scan text for profanity using the Bad Word Filter or sanitize untrusted HTML to ensure safe, presentable content anywhere it’s needed.
Security and risk assessment: Automate reputation checks on hosts and domains, enabling your agent to proactively identify potential threats or block risky sources without manual effort.
Currency and unit conversion: Empower your agent to convert between different units or currencies on demand, streamlining financial or scientific operations with ease.

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:

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

Step-by-step Guide

Step by step10 STEPS

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

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.

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

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

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 Neutrino functionality through MCP

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 Neutrino tools
Validating that COMPOSIO_USER_ID is also set before proceeding

Create a Tool Router session

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

const url = session.mcp.url;

What's happening:

We're creating a Tool Router session that gives your agent access to Neutrino 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 Neutrino tools as needed

Configure the agent with the MCP URL

const client = new MultiServerMCPClient({
    "neutrino-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 Neutrino MCP server via HTTP
The client is configured with a name and the URL from our Tool Router session
getTools() retrieves all available Neutrino tools that the agent can use
We're creating a LangChain agent using the GPT-5 model

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 Neutrino 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

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 Neutrino 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: ['neutrino']
        }
    );

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

Add Watermark to Image

Add a watermark to an image with customizable position, opacity, and output format.

Bad Word Filter

Tool to detect bad words and profanity in text.

BIN Lookup

Perform a BIN (Bank Identification Number) lookup to retrieve comprehensive card issuer information.

IP Blocklist

Check if an IP address is on a blocklist.

Convert Value

Tool to perform unit and currency conversions.

Validate and analyze an email address

Validates and analyzes email addresses for syntax, domain validity, DNS/MX records, and detects freemail/disposable providers.

Verify Email Address

Tool to verify and analyze the deliverability of an email address.

Geocode Address

Tool to geocode an address.

Reverse Geocode

Convert geographic coordinates (latitude/longitude) into real-world address information.

HLR Lookup

Perform real-time HLR (Home Location Register) lookup to validate mobile numbers and retrieve detailed network information.

Host Reputation

Check if an IP address, domain, or URL is listed on DNS-based Blackhole Lists (DNSBLs).

HTML Clean

Tool to clean and sanitize untrusted HTML.

HTML Render

Render HTML content to PDF, PNG, or JPG format.

Resize Image

Resize, crop, and convert images to PNG or JPG format.

IP Info

Get comprehensive geolocation and network information for an IPv4 or IPv6 address.

IP Probe

Analyzes an IPv4 or IPv6 address to extract detailed network intelligence including geolocation, ISP/hosting provider information, ASN details, and security flags (VPN, proxy, TOR detection).

Domain Lookup

Tool to perform a domain lookup to retrieve WHOIS, DNS records, domain registration information and detect potentially malicious or dangerous domains.

Phone Validate

Tool to validate and lookup phone numbers.

QR Code

Generate a QR code or Code 128 barcode as a PNG image.

Browser Bot

Tool to automate browser interactions using a real Chromium browser.

SMS Verify

Tool to send a unique security code via SMS.

UA Lookup

Parse and analyze User-Agent strings to extract detailed browser, device, and operating system information.

URL Info

Tool to parse, analyze, and retrieve content from the supplied URL.

Verify Security Code

Verify a security code generated by SMS Verify or Phone Verify APIs.

FRAMEWORKS

How to build Neutrino MCP Agent with another framework

OpenAI Agents SDK

Use Neutrino MCP with OpenAI Agents SDK

Claude Agent SDK

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Claude Code

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Claude Cowork

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Codex

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OpenClaw

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Hermes

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CLI

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Google ADK

Use Neutrino MCP with Google ADK

Vercel AI SDK

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Mastra AI

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LlamaIndex

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CrewAI

Use Neutrino MCP with CrewAI

MORE TOOLKITS

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Abstract

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Addressfinder

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Addressfinder is a data quality platform for verifying addresses, emails, and phone numbers. It helps you ensure accurate customer and contact data every time.

FAQ

Frequently asked questions

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

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

Start with Neutrino.It takes 30 seconds.

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

Start building

Customer stories

Teams ship real agents on Composio

GET STARTED FOR FREE BOOK A DEMO

Karan skipped his own birthday party to fix our critical issue. It was 10pm and he diverted his Waymo to help us instead. This really sets the bar — it shows the commitment you need when users rely on your software.

Harsha Gaddipati

Co-founder, Slashy

A lot of students tell us that the moment their connected tools start talking to each other inside Opennote feels almost magical. The agent just knows them, and it's immensely helped keep new users on the platform.

Abhi Arya

Co-founder, Opennote

We chose Composio over Pipedream because it delivered depth where it mattered — niche tools and tricky edge cases other platforms simply ignored. That gave us confidence to scale without compromising.

Nirman Dave

CEO, Zams

As a solo builder, shipping fast is life or death. The only way I can outcompete incumbents is by outmanoeuvring them. Getting bogged down managing agent auth would have been a death sentence.

Ryan Yu

Founder, Extra Thursday

Before Composio, adding tool integrations was slow and resource-intensive. Each one could take weeks of engineering time, and maintaining them meant constantly keeping up with API changes.

Tomisin Jenrola

Founder & CEO, SwarmZero

With hands-on help from their founder, we integrated Gmail and Google Drive in just 30 minutes. This level of personal support and commitment is exactly what startups should strive for.

Jerome Leclanche

Co-Founder, Ingram Technologies

How to integrate Neutrino MCP with LangChain

Connect Neutrino without auth hassles

Introduction

Also integrate Neutrino with

TL;DR

What is LangChain?

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

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

What is Composio SDK?

How the Composio SDK works

Step-by-step Guide

Prerequisites

Getting API Keys for OpenAI and Composio

Install dependencies

Set up environment variables

Import dependencies

Initialize Composio client

Create a Tool Router session

Configure the agent with the MCP URL

Set up interactive chat interface

Run the application

Complete Code

Conclusion

Supported Tools

How to build Neutrino MCP Agent with another framework

OpenAI Agents SDK

Claude Agent SDK

Claude Code

Claude Cowork

Codex

OpenClaw

Hermes

CLI

Google ADK

Vercel AI SDK

Mastra AI

LlamaIndex

CrewAI

Explore Other Toolkits

Excel

21risk

Abstract

Addressfinder

Frequently asked questions

What are the differences in Tool Router MCP and Neutrino MCP?+

Can I use Tool Router MCP with LangChain?+

Can I manage the permissions and scopes for Neutrino while using Tool Router?+

How safe is my data with Composio Tool Router?+

Start with Neutrino.It takes 30 seconds.

Teams ship real agents on Composio