# How to integrate Marketstack MCP with LangChain

```json
{
  "title": "How to integrate Marketstack MCP with LangChain",
  "toolkit": "Marketstack",
  "toolkit_slug": "marketstack",
  "framework": "LangChain",
  "framework_slug": "langchain",
  "url": "https://composio.dev/toolkits/marketstack/framework/langchain",
  "markdown_url": "https://composio.dev/toolkits/marketstack/framework/langchain.md",
  "updated_at": "2026-03-29T06:41:39.139Z"
}
```

## Introduction

This guide walks you through connecting Marketstack to LangChain using the Composio tool router. By the end, you'll have a working Marketstack agent that can get the latest price for aapl, show historical prices for tsla last month, list top gainers on nyse today through natural language commands.
This guide will help you understand how to give your LangChain agent real control over a Marketstack account through Composio's Marketstack MCP server.
Before we dive in, let's take a quick look at the key ideas and tools involved.

## Also integrate Marketstack with

- [OpenAI Agents SDK](https://composio.dev/toolkits/marketstack/framework/open-ai-agents-sdk)
- [Claude Agent SDK](https://composio.dev/toolkits/marketstack/framework/claude-agents-sdk)
- [Claude Code](https://composio.dev/toolkits/marketstack/framework/claude-code)
- [Claude Cowork](https://composio.dev/toolkits/marketstack/framework/claude-cowork)
- [Codex](https://composio.dev/toolkits/marketstack/framework/codex)
- [OpenClaw](https://composio.dev/toolkits/marketstack/framework/openclaw)
- [Hermes](https://composio.dev/toolkits/marketstack/framework/hermes-agent)
- [CLI](https://composio.dev/toolkits/marketstack/framework/cli)
- [Google ADK](https://composio.dev/toolkits/marketstack/framework/google-adk)
- [Vercel AI SDK](https://composio.dev/toolkits/marketstack/framework/ai-sdk)
- [Mastra AI](https://composio.dev/toolkits/marketstack/framework/mastra-ai)
- [LlamaIndex](https://composio.dev/toolkits/marketstack/framework/llama-index)
- [CrewAI](https://composio.dev/toolkits/marketstack/framework/crew-ai)

## TL;DR

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

The Marketstack MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Marketstack account. It provides structured and secure access so your agent can perform Marketstack operations on your behalf.

## Supported Tools

| Tool slug | Name | Description |
|---|---|---|
| `MARKETSTACK_GET_DIVIDENDS` | Get Dividends | Tool to retrieve stock dividend data for one or more ticker symbols from Marketstack API. Use when you need historical dividend payment information for stocks, including dividend amounts and payment dates. |
| `MARKETSTACK_GET_EOD` | Get End-of-Day Data | Tool to retrieve end-of-day (EOD) stock data for one or multiple ticker symbols. Returns OHLCV data (open, high, low, close, volume) along with adjusted prices, dividends, and split factors. Use when you need historical daily stock prices or market data analysis. |
| `MARKETSTACK_GET_EXCHANGE` | Get Exchange Info | Tool to retrieve detailed information for a specific stock exchange by its MIC (Market Identifier Code). Use when you need comprehensive information about an exchange including its location, status, and operational details. |
| `MARKETSTACK_GET_SPLITS` | Get Stock Splits | Tool to retrieve stock split data for one or more stock symbols from Marketstack. Use when you need historical split information including split factors and dates. |
| `MARKETSTACK_GET_TICKER_EOD_DATA` | Get Ticker EOD Data | Tool to retrieve end-of-day stock price data for a specific ticker symbol. Use when you need historical daily price information including open, high, low, close, volume, and adjusted values. |
| `MARKETSTACK_GET_TICKER_EOD_LATEST` | Get Ticker EOD Latest | Tool to retrieve end-of-day (EOD) stock data for the latest available date for a specific ticker. Use when you need the most recent trading day data for a stock symbol. |
| `MARKETSTACK_GET_TICKER_INFO` | Get Ticker Info | Tool to retrieve detailed information about stock tickers including exchange, sector, and industry data. Use when you need comprehensive company information for a ticker symbol. |
| `MARKETSTACK_LIST_CURRENCIES` | List Currencies | Tool to retrieve a list of all supported currencies from the Marketstack API. Use when you need to get information about available currencies for stock market data. |
| `MARKETSTACK_LIST_STOCK_EXCHANGES` | List Stock Exchanges | Tool to retrieve information about supported stock exchanges. Use when you need to list or search for stock exchanges from the 2700+ exchanges available in Marketstack. |
| `MARKETSTACK_LIST_TICKERS` | List Tickers | Tool to get a list of all supported stock tickers. Use when you need to obtain the full list of tickers supported by Marketstack or search for specific tickers. |

## Supported Triggers

None listed.

## Creating MCP Server - Stand-alone vs Composio SDK

The Marketstack MCP server is an implementation of the Model Context Protocol that connects your AI agent to Marketstack. It provides structured and secure access so your agent can perform Marketstack operations on your behalf through a secure, permission-based interface.
With Composio's managed implementation, you don't have to create your own developer app. For production, if you're building an end product, we recommend using your own credentials. The managed server helps you prototype fast and go from 0-1 faster.

## Step-by-step Guide

### 1. Prerequisites

No description provided.

### 1. Getting API Keys for OpenAI and Composio

OpenAI API Key
- Go to the [OpenAI dashboard](https://platform.openai.com/settings/organization/api-keys) 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](https://dashboard.composio.dev?utm_source=toolkits&utm_medium=framework_docs).
- Navigate to your API settings and generate a new API key.
- Store this key securely as you'll need it for authentication.

### 2. Install dependencies

No description provided.
```python
pip install composio-langchain langchain-mcp-adapters langchain python-dotenv
```

```typescript
npm install @composio/langchain @langchain/core @langchain/openai @langchain/mcp-adapters dotenv
```

### 3. Set up environment variables

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
```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
```

### 4. Import dependencies

No description provided.
```python
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()
```

```typescript
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();
```

### 5. Initialize Composio client

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 Marketstack tools
- Validating that COMPOSIO_USER_ID is also set before proceeding
```python
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")
```

```typescript
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()
    });
```

### 6. Create a Tool Router session

What's happening:
- We're creating a Tool Router session that gives your agent access to Marketstack 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 Marketstack tools as needed
```python
# Create Tool Router session for Marketstack
session = composio.create(
    user_id=os.getenv("COMPOSIO_USER_ID"),
    toolkits=['marketstack']
)

url = session.mcp.url
```

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

const url = session.mcp.url;
```

### 7. Configure the agent with the MCP URL

No description provided.
```python
client = MultiServerMCPClient({
    "marketstack-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)
```

```typescript
const client = new MultiServerMCPClient({
    "marketstack-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 });
```

### 8. Set up interactive chat interface

No description provided.
```python
conversation_history = []

print("Chat started! Type 'exit' or 'quit' to end the conversation.\n")
print("Ask any Marketstack 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")
```

```typescript
let conversationHistory: any[] = [];

console.log("Chat started! Type 'exit' or 'quit' to end the conversation.\n");
console.log("Ask any Marketstack 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);
    });
```

### 9. Run the application

No description provided.
```python
if __name__ == "__main__":
    asyncio.run(main())
```

```typescript
main().catch((err) => {
    console.error('Fatal error:', err);
    process.exit(1);
});
```

## Complete Code

```python
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=['marketstack']
    )

    url = session.mcp.url
    
    client = MultiServerMCPClient({
        "marketstack-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 Marketstack 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())
```

```typescript
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: ['marketstack']
        }
    );

    const url = session.mcp.url;
    
    const client = new MultiServerMCPClient({
        "marketstack-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 Marketstack 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 Marketstack 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 Marketstack MCP Agent with another framework

- [OpenAI Agents SDK](https://composio.dev/toolkits/marketstack/framework/open-ai-agents-sdk)
- [Claude Agent SDK](https://composio.dev/toolkits/marketstack/framework/claude-agents-sdk)
- [Claude Code](https://composio.dev/toolkits/marketstack/framework/claude-code)
- [Claude Cowork](https://composio.dev/toolkits/marketstack/framework/claude-cowork)
- [Codex](https://composio.dev/toolkits/marketstack/framework/codex)
- [OpenClaw](https://composio.dev/toolkits/marketstack/framework/openclaw)
- [Hermes](https://composio.dev/toolkits/marketstack/framework/hermes-agent)
- [CLI](https://composio.dev/toolkits/marketstack/framework/cli)
- [Google ADK](https://composio.dev/toolkits/marketstack/framework/google-adk)
- [Vercel AI SDK](https://composio.dev/toolkits/marketstack/framework/ai-sdk)
- [Mastra AI](https://composio.dev/toolkits/marketstack/framework/mastra-ai)
- [LlamaIndex](https://composio.dev/toolkits/marketstack/framework/llama-index)
- [CrewAI](https://composio.dev/toolkits/marketstack/framework/crew-ai)

## Related Toolkits

- [Firecrawl](https://composio.dev/toolkits/firecrawl) - Firecrawl automates large-scale web crawling and data extraction. It helps organizations efficiently gather, index, and analyze content from online sources.
- [Tavily](https://composio.dev/toolkits/tavily) - Tavily offers powerful search and data retrieval from documents, databases, and the web. It helps teams locate and filter information instantly, saving hours on research.
- [Exa](https://composio.dev/toolkits/exa) - Exa is a data extraction and search platform for gathering and analyzing information from websites, APIs, or databases. It helps teams quickly surface insights and automate data-driven workflows.
- [Serpapi](https://composio.dev/toolkits/serpapi) - SerpApi is a real-time API for structured search engine results. It lets you automate SERP data collection, parsing, and analysis for SEO and research.
- [Peopledatalabs](https://composio.dev/toolkits/peopledatalabs) - Peopledatalabs delivers B2B data enrichment and identity resolution APIs. Supercharge your apps with accurate, up-to-date business and contact data.
- [Stripe](https://composio.dev/toolkits/stripe) - Stripe is a global online payments platform offering APIs for managing payments, customers, and subscriptions. Trusted by businesses for secure, efficient, and scalable payment processing worldwide.
- [Snowflake](https://composio.dev/toolkits/snowflake) - Snowflake is a cloud data warehouse built for elastic scaling, secure data sharing, and fast SQL analytics across major clouds.
- [Posthog](https://composio.dev/toolkits/posthog) - PostHog is an open-source analytics platform for tracking user interactions and product metrics. It helps teams refine features, analyze funnels, and reduce churn with actionable insights.
- [Alpha vantage](https://composio.dev/toolkits/alpha_vantage) - Alpha Vantage is a financial data platform offering real-time and historical stock market APIs. Get instant, reliable access to equities, forex, and technical analysis data for smarter trading decisions.
- [Altoviz](https://composio.dev/toolkits/altoviz) - Altoviz is a cloud-based billing and invoicing platform for businesses. It streamlines online payments, expense tracking, and customizable invoice management.
- [Amplitude](https://composio.dev/toolkits/amplitude) - Amplitude is a digital analytics platform for product and behavioral data insights. It helps teams analyze user journeys and make data-driven decisions quickly.
- [Benzinga](https://composio.dev/toolkits/benzinga) - Benzinga provides real-time financial news and data APIs for market coverage. It helps you track breaking news and actionable market insights instantly.
- [Brex](https://composio.dev/toolkits/brex) - Brex provides corporate credit cards and spend management tailored for startups and tech businesses. It helps optimize company cash flow, streamline accounting, and accelerate business growth.
- [Bright Data MCP](https://composio.dev/toolkits/brightdata_mcp) - Bright Data MCP is an AI-powered web scraping and data collection platform. Instantly access public web data in real time with advanced scraping tools.
- [Browseai](https://composio.dev/toolkits/browseai) - Browseai is a web automation and data extraction platform that turns any website into an API. It's perfect for monitoring websites and retrieving structured data without manual scraping.
- [Chaser](https://composio.dev/toolkits/chaser) - Chaser is accounts receivable automation software that sends invoice reminders and helps businesses get paid faster. It streamlines the collections process to save time and improve cash flow.
- [ClickHouse](https://composio.dev/toolkits/clickhouse) - ClickHouse is an open-source, column-oriented database for real-time analytics and big data processing using SQL. Its lightning-fast query performance makes it ideal for handling large datasets and delivering instant insights.
- [Clientary](https://composio.dev/toolkits/clientary) - Clientary is a platform for managing clients, invoices, projects, proposals, and more. It streamlines client work and saves you serious admin time.
- [Coinbase](https://composio.dev/toolkits/coinbase) - Coinbase is a platform for buying, selling, and storing cryptocurrency. It makes exchanging and managing crypto simple and secure for everyone.
- [Coinmarketcal](https://composio.dev/toolkits/coinmarketcal) - CoinMarketCal is a community-powered crypto calendar for upcoming events, announcements, and releases. It helps traders track market-moving developments and stay ahead in the crypto space.

## Frequently Asked Questions

### What are the differences in Tool Router MCP and Marketstack MCP?

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

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

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

---
[See all toolkits](https://composio.dev/toolkits) · [Composio docs](https://docs.composio.dev/llms.txt)