How to integrate Crustdata MCP with LangChain

BOOK A CALLGET STARTED FOR FREE
Framework Integration Gradient
Crustdata Logo
LangChain Logo
divider

Introduction

This guide walks you through connecting Crustdata to LangChain using the Composio tool router. By the end, you'll have a working Crustdata agent that can find tech companies with recent funding milestones, enrich this lead's profile with latest data, list top decision makers in saas startups, fetch job listings for fortune 500 companies through natural language commands.

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

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

TL;DR

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

The Crustdata MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Crustdata account. It provides structured and secure access to real-time company and people intelligence, so your agent can perform actions like lead enrichment, market research, investor portfolio analysis, and workforce trend tracking on your behalf.

  • Comprehensive person and company enrichment: Instantly enrich leads or companies with up-to-date details for customer profiling, data verification, or targeted outreach.
  • Advanced decision maker filtering: Find and analyze decision makers across organizations using complex filters, titles, and segmentation for your sales or marketing efforts.
  • Investor portfolio and funding milestone analysis: Retrieve in-depth investor portfolio data, analyze funding milestones, and generate reports for investment research or deal sourcing.
  • Workforce and job market trend insights: Fetch headcount and job listing timeseries data to track organizational growth, hiring activity, or competitive shifts in specific industries.
  • Social and web activity monitoring: Collect and analyze LinkedIn posts and web traffic data for any company to assess engagement, sentiment, and digital footprint for market intelligence and outreach strategies.

Supported Tools & Triggers

Tools
Enrich person screenerThe screener person enrich endpoint enriches person data by providing additional information based on the given query.
Fetch headcount by facet timeseriesRetrieves headcount data as a timeseries with faceted analysis capabilities.
Fetch investor portfolio dataRetrieves comprehensive investor portfolio data from the data lab section of the crustdata api.
Filter decision makers dataFilters and retrieves decision maker data from the crustdata b2b saas integration platform based on complex criteria.
Post funding milestone timeseries dataThe fundingmilestonetimeseries endpoint retrieves time-series data related to funding milestones for companies.
Post headcount timeseries dataRetrieves filtered and sorted headcount timeseries data from the crustdata data lab.
Post job listings table dataThis endpoint retrieves filtered and sorted job listings data for specified company tickers from a chosen dataset in the crustdata platform.
Post web traffic dataRetrieves filtered and sorted web traffic data from the crustdata platform.
Retrieve linkedin postsRetrieves linkedin posts for a specified company using crustdata's screener functionality.
Screener company informationThe getcompanyscreener endpoint allows users to search and filter companies based on various criteria such as headcount, growth rate, funding, and more.
Screen metrics and filter conditionsThe screendata endpoint enables advanced data screening and filtering on the crustdata platform.
Search companies with filtersThe companysearch endpoint enables users to search and filter companies using the crustdata api.
Search for job id in screenerThe screener person search endpoint allows users to search for persons associated with a specific job id within the crustdata b2b saas integration platform.
Search linkedin posts by keywordThis endpoint enables searching for linkedin posts using a specific keyword.

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

What is Tool Router?

Composio's Tool Router 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 Tool Router

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

How the Tool Router works

The Tool Router 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

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

pip install composio-langchain langchain-mcp-adapters langchain python-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 is the core agent framework
  • python-dotenv 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

from langchain_mcp_adapters.client import MultiServerMCPClient
from langchain.agents import create_agent
from dotenv import load_dotenv
from composio import Composio
import asyncio
import os

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

Initialize Composio client

async def main():
    composio = Composio(api_key=os.getenv("COMPOSIO_API_KEY"))

    if not os.getenv("COMPOSIO_API_KEY"):
        raise ValueError("COMPOSIO_API_KEY is not set")
    if not os.getenv("COMPOSIO_USER_ID"):
        raise ValueError("COMPOSIO_USER_ID is not set")
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 Crustdata tools
  • Validating that COMPOSIO_USER_ID is also set before proceeding

Create a Tool Router session

# Create Tool Router session for Crustdata
session = composio.create(
    user_id=os.getenv("COMPOSIO_USER_ID"),
    toolkits=['crustdata']
)

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

Configure the agent with the MCP URL

client = MultiServerMCPClient({
    "crustdata-agent": {
        "transport": "streamable_http",
        "url": session.mcp.url,
        "headers": {
            "x-api-key": os.getenv("COMPOSIO_API_KEY")
        }
    }
})

tools = await client.get_tools()

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

Set up interactive chat interface

conversation_history = []

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

while True:
    user_input = input("You: ").strip()

    if user_input.lower() in ['exit', 'quit', 'bye']:
        print("\nGoodbye!")
        break

    if not user_input:
        continue

    conversation_history.append({"role": "user", "content": user_input})
    print("\nAgent is thinking...\n")

    response = await agent.ainvoke({"messages": conversation_history})
    conversation_history = response['messages']
    final_response = response['messages'][-1].content
    print(f"Agent: {final_response}\n")
What's happening:
  • We initialize an empty conversation_history list to maintain context across interactions
  • A while loop continuously accepts 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 ainvoke() method with the full conversation history
  • Users can type 'exit', 'quit', or 'bye' to end the chat session gracefully

Run the application

if __name__ == "__main__":
    asyncio.run(main())
What's happening:
  • We call the main() function using asyncio.run() to start the application

Complete Code

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

from langchain_mcp_adapters.client import MultiServerMCPClient
from langchain.agents import create_agent
from dotenv import load_dotenv
from composio import Composio
import asyncio
import os

load_dotenv()

async def main():
    composio = Composio(api_key=os.getenv("COMPOSIO_API_KEY"))
    
    if not os.getenv("COMPOSIO_API_KEY"):
        raise ValueError("COMPOSIO_API_KEY is not set")
    if not os.getenv("COMPOSIO_USER_ID"):
        raise ValueError("COMPOSIO_USER_ID is not set")
    
    session = composio.create(
        user_id=os.getenv("COMPOSIO_USER_ID"),
        toolkits=['crustdata']
    )

    url = session.mcp.url
    
    client = MultiServerMCPClient({
        "crustdata-agent": {
            "transport": "streamable_http",
            "url": url,
            "headers": {
                "x-api-key": os.getenv("COMPOSIO_API_KEY")
            }
        }
    })
    
    tools = await client.get_tools()
  
    agent = create_agent("gpt-5", tools)
    
    conversation_history = []
    
    print("Chat started! Type 'exit' or 'quit' to end the conversation.\n")
    print("Ask any Crustdata related question or task to the agent.\n")
    
    while True:
        user_input = input("You: ").strip()
        
        if user_input.lower() in ['exit', 'quit', 'bye']:
            print("\nGoodbye!")
            break
        
        if not user_input:
            continue
        
        conversation_history.append({"role": "user", "content": user_input})
        print("\nAgent is thinking...\n")
        
        response = await agent.ainvoke({"messages": conversation_history})
        conversation_history = response['messages']
        final_response = response['messages'][-1].content
        print(f"Agent: {final_response}\n")

if __name__ == "__main__":
    asyncio.run(main())

Conclusion

You've successfully built a LangChain agent that can interact with Crustdata 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.

How to build Crustdata MCP Agent with another framework

OpenAI Agents SDK

OpenAI Agents SDK

Use Crustdata MCP with OpenAI Agents SDK

Claude Agent SDK

Claude Agent SDK

Use Crustdata MCP with Claude Agent SDK

Google ADK

Google ADK

Use Crustdata MCP with Google ADK

Vercel AI SDK

Vercel AI SDK

Use Crustdata MCP with Vercel AI SDK

Mastra AI

Mastra AI

Use Crustdata MCP with Mastra AI

LlamaIndex

LlamaIndex

Use Crustdata MCP with LlamaIndex

CrewAI

CrewAI

Use Crustdata MCP with CrewAI

FAQ

What are the differences in Tool Router MCP and Crustdata MCP?

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

Can I use Tool Router MCP with LangChain?

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 Crustdata tools.

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

Yes, absolutely. You can configure which Crustdata 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.

How safe is my data with Composio Tool Router?

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 Crustdata data and credentials are handled as safely as possible.

Used by agents from

Context
ASU
Letta
glean
HubSpot
Agent.ai
Altera
DataStax
Entelligence
Rolai
Context
ASU
Letta
glean
HubSpot
Agent.ai
Altera
DataStax
Entelligence
Rolai
Context
ASU
Letta
glean
HubSpot
Agent.ai
Altera
DataStax
Entelligence
Rolai

Never worry about agent reliability

We handle tool reliability, observability, and security so you never have to second-guess an agent action.

Book a call↗Get started for free