How to integrate Diffbot MCP with LangChain

This guide walks you through connecting Diffbot to LangChain using the Composio tool router. By the end, you'll have a working Diffbot agent that can extract specs and reviews from a product page, summarize key details from a news article url, list all bulk data extraction jobs for your account through natural language commands. This guide will help you understand how to give your LangChain agent real control over a Diffbot account through Composio's Diffbot MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved.

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Diffbot

Api Key

Diffbot is an AI-powered platform for extracting and structuring data from any web page. It transforms unstructured web content into rich, linked, and queryable data for analytics, research, and automation.

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Introduction

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

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

Also integrate Diffbot 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 Diffbot project to Composio
Create a Tool Router MCP session for Diffbot
Initialize an MCP client and retrieve Diffbot tools
Build a LangChain agent that can interact with Diffbot
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 Diffbot MCP server, and what's possible with it?

The Diffbot MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Diffbot account. It provides structured and secure access to web data extraction and analysis, so your agent can extract structured data from web pages, analyze content types, retrieve product details, manage bulk jobs, and search extracted datasets on your behalf.

Automatic content analysis and extraction: Let your agent analyze any web page and automatically extract structured data such as articles, products, events, images, or videos using AI-powered tools.
Article and discussion thread extraction: Effortlessly pull detailed metadata, authors, publication dates, and full discussion threads from news sites, blogs, forums, and comment sections.
Product and event data gathering: Instantly extract comprehensive product specifications, pricing, reviews, and event information including venues, dates, and descriptions from e-commerce or event pages.
Bulk job management and search: Enable your agent to list, monitor, and search across large-scale crawl or extraction jobs, making it easy to work with massive web data collections.
Account and usage insights: Retrieve your Diffbot account details, plan information, and usage statistics to stay on top of quotas and manage your web data operations efficiently.

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 Diffbot 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 Diffbot 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: ['diffbot']
    }
);

const url = session.mcp.url;

What's happening:

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

Configure the agent with the MCP URL

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

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

Combine Entity Profiles

Combine multiple entity profiles into a unified view using the Diffbot Knowledge Graph.

Create Bulk Extract Job

Tool to submit a bulk extract job to process multiple URLs with Extract APIs.

Create or Update Custom API

Tool to create or update the parameters and ruleset of a Custom API.

Create Bulk Enhance Job

Tool to submit a bulk enhance job to enrich multiple entities asynchronously.

Delete Custom API

Tool to delete custom API definitions for a given URL pattern.

Delete KG Enhance Bulkjob

Tool to delete an Enhance Bulkjob.

Download Bulk Job Results

Tool to download results of a bulk enhance job with filtering options via POST request.

Enhance Entity with Knowledge Graph

Enrich a person or organization with comprehensive data from the Diffbot Knowledge Graph.

Diffbot Extract Job

Tool to extract structured job posting data from job listing pages.

Diffbot Extract List

Tool to extract structured data from list-style pages like news indexes, product listings, and directory pages.

Get Diffbot Account Details

Retrieves comprehensive Diffbot account information including subscription plan details, credit balance, usage history, and account status.

Diffbot Analyze

Automatically analyzes a web page to determine its type and extract structured data.

Get Article Data

Tool to extract information from articles, including authors, publication dates, and images.

Get Bulk Job Data

Tool to download extracted results from a completed bulk job.

Get Bulk Job Status

Tool to poll the status of a specific Diffbot Knowledge Graph Enhance bulk job.

Get Bulk Job Results

Tool to download the results of a completed Enhance Bulkjob.

Get Bulk Single Result

Tool to download the result of a single job within a Diffbot bulk enhance job.

Get Crawl Data

Download extracted results from a completed crawl job.

Get Discussion Thread

Extract structured discussion threads from web pages including forums, comment sections, product reviews, Reddit discussions, and blog comments.

Diffbot Get Event

Tool to extract event details from web pages.

Diffbot Get Image

Tool to extract detailed information about images, including dimensions and recognition data.

Get KG Coverage Report by ID

Download Knowledge Graph coverage report by report ID.

Diffbot Get Product

Tool to extract product information such as specifications, prices, availability, and reviews.

Get Video Data

Tool to extract information from videos, including titles, descriptions, and embedded HTML.

List Bulk Jobs

Tool to list all Bulk jobs associated with a specific token.

List Bulk Jobs Status For Token

Tool to get the status of all bulk enhance jobs for a token.

List Custom APIs

Tool to retrieve all Custom APIs and their extraction rules currently defined on your Diffbot token.

Manage Crawl Job

Manages Diffbot crawl jobs: pause, restart, delete, or view status.

Resolve Lost ID

Tool to resolve lost IDs in the Knowledge Graph.

Diffbot Knowledge Graph Search

Search the Diffbot Knowledge Graph using DQL (Diffbot Query Language).

Search Crawl Job Data

Tool to query crawl job collections using DQL (Diffbot Query Language).

Start Bulk Job

Tool to start a Bulk Extract job.

Start Crawl Job

Initiates a Diffbot crawl job that spiders a website starting from seed URLs and processes discovered pages with a specified Extract API.

Stop Bulk Job

Tool to pause (stop) a running Bulk job.

Stop KG Bulk Job By ID

Tool to stop an active Knowledge Graph Enhance bulk job by its ID.

FRAMEWORKS

How to build Diffbot MCP Agent with another framework

OpenAI Agents SDK

Use Diffbot MCP with OpenAI Agents SDK

Claude Agent SDK

Use Diffbot MCP with Claude Agent SDK

Claude Code

Use Diffbot MCP with Claude Code

Claude Cowork

Use Diffbot MCP with Claude Cowork

Codex

Use Diffbot MCP with Codex

OpenClaw

Use Diffbot MCP with OpenClaw

Hermes

Use Diffbot MCP with Hermes

CLI

Use Diffbot MCP with CLI

Google ADK

Use Diffbot MCP with Google ADK

Vercel AI SDK

Use Diffbot MCP with Vercel AI SDK

Mastra AI

Use Diffbot MCP with Mastra AI

LlamaIndex

Use Diffbot MCP with LlamaIndex

CrewAI

Use Diffbot MCP with CrewAI

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FAQ

Frequently asked questions

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

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

Start with Diffbot.It takes 30 seconds.

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

Start building

Customer stories

Teams ship real agents on Composio

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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 Diffbot MCP with LangChain

Connect Diffbot without auth hassles

Introduction

Also integrate Diffbot with

TL;DR

What is LangChain?

What is the Diffbot 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 Diffbot 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 Diffbot MCP?+

Can I use Tool Router MCP with LangChain?+

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

How safe is my data with Composio Tool Router?+

Start with Diffbot.It takes 30 seconds.

Teams ship real agents on Composio