How to integrate Mx toolbox MCP with OpenAI Agents SDK

This guide walks you through connecting Mx toolbox to the OpenAI Agents SDK using the Composio tool router. By the end, you'll have a working Mx toolbox agent that can check if your domain is blacklisted, get current mx records for example.com, run a ping test on our mail server through natural language commands. This guide will help you understand how to give your OpenAI Agents SDK agent real control over a Mx toolbox account through Composio's Mx toolbox MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved.

Mx toolbox logoMx toolbox
Api Key

MxToolbox is a network diagnostic and monitoring service with advanced DNS, blacklist, and email health tools. It helps IT teams quickly troubleshoot and ensure reliable email and network performance.

13 Tools

Introduction

This guide walks you through connecting Mx toolbox to the OpenAI Agents SDK using the Composio tool router. By the end, you'll have a working Mx toolbox agent that can check if your domain is blacklisted, get current mx records for example.com, run a ping test on our mail server through natural language commands.

This guide will help you understand how to give your OpenAI Agents SDK agent real control over a Mx toolbox account through Composio's Mx toolbox MCP server.

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

Also integrate Mx toolbox with

TL;DR

Here's what you'll learn:
  • Get and set up your OpenAI and Composio API keys
  • Install the necessary dependencies
  • Initialize Composio and create a Tool Router session for Mx toolbox
  • Configure an AI agent that can use Mx toolbox as a tool
  • Run a live chat session where you can ask the agent to perform Mx toolbox operations

What is OpenAI Agents SDK?

The OpenAI Agents SDK is a lightweight framework for building AI agents that can use tools and maintain conversation state. It provides a simple interface for creating agents with hosted MCP tool support.

Key features include:

  • Hosted MCP Tools: Connect to external services through hosted MCP endpoints
  • SQLite Sessions: Persist conversation history across interactions
  • Simple API: Clean interface with Agent, Runner, and tool configuration
  • Streaming Support: Real-time response streaming for interactive applications

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

The Mx toolbox MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Mx toolbox account. It provides structured and secure access to network diagnostic and email health tools, so your agent can perform actions like DNS lookups, blacklist checks, email authentication analysis, and connectivity testing on your behalf.

  • Automated DNS and MX record lookups: Instantly retrieve DNS, MX, DKIM, DMARC, and MTA-STS records for any domain to verify configuration and troubleshoot email delivery issues.
  • Blacklist monitoring and alerting: Check if your domain or IP is listed on common blacklists, helping you stay ahead of email deliverability problems and security risks.
  • Email authentication validation: Validate BIMI, DKIM, and DMARC records to ensure your domain's outgoing emails are properly authenticated and protected against spoofing.
  • Network and SMTP diagnostics: Run ping, HTTP, and SMTP lookups to diagnose connectivity issues, measure latency, or assess mail server responsiveness—no manual testing required.
  • Brand and security checks: Use BIMI and MTA-STS lookups to confirm your brand indicators and mail transport security policies are correctly published and compliant.

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 step09 STEPS
1

Prerequisites

Before starting, make sure you have:
  • Composio API Key and OpenAI API Key
  • Primary know-how of OpenAI Agents SDK
  • A live Mx toolbox project
  • Some knowledge of Python or Typescript
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
3

Install dependencies

npm install @composio/openai-agents @openai/agents dotenv

Install the Composio SDK and the OpenAI Agents SDK.

4

Set up environment variables

bash
OPENAI_API_KEY=sk-...your-api-key
COMPOSIO_API_KEY=your-api-key
USER_ID=composio_user@gmail.com

Create a .env file and add your OpenAI and Composio API keys.

5

Import dependencies

import 'dotenv/config';
import { Composio } from '@composio/core';
import { OpenAIAgentsProvider } from '@composio/openai-agents';
import { Agent, hostedMcpTool, run, OpenAIConversationsSession } from '@openai/agents';
import * as readline from 'readline';
What's happening:
  • You're importing all necessary libraries.
  • The Composio and OpenAIAgentsProvider classes are imported to connect your OpenAI agent to Composio tools like Mx toolbox.
6

Set up the Composio instance

dotenv.config();

const composioApiKey = process.env.COMPOSIO_API_KEY;
const userId = process.env.USER_ID;

if (!composioApiKey) {
  throw new Error('COMPOSIO_API_KEY is not set. Create a .env file with COMPOSIO_API_KEY=your_key');
}
if (!userId) {
  throw new Error('USER_ID is not set');
}

// Initialize Composio
const composio = new Composio({
  apiKey: composioApiKey,
  provider: new OpenAIAgentsProvider(),
});
What's happening:
  • dotenv.config() loads your .env file so COMPOSIO_API_KEY and USER_ID are available as environment variables.
  • Creating a Composio instance using the API Key and OpenAIAgentsProvider class.
7

Create a Tool Router session

// Create Tool Router session for Mx toolbox
const session = await composio.create(userId as string, {
  toolkits: ['mx_toolbox'],
});
const mcpUrl = session.mcp.url;

What is happening:

  • You give the Tool Router the user id and the toolkits you want available. Here, it is only mx_toolbox.
  • The router checks the user's Mx toolbox connection and prepares the MCP endpoint.
  • The returned session.mcp.url is the MCP URL that your agent will use to access Mx toolbox.
  • This approach keeps things lightweight and lets the agent request Mx toolbox tools only when needed during the conversation.
8

Configure the agent

// Configure agent with MCP tool
const agent = new Agent({
  name: 'Assistant',
  model: 'gpt-5',
  instructions:
    'You are a helpful assistant that can access Mx toolbox. Help users perform Mx toolbox operations through natural language.',
  tools: [
    hostedMcpTool({
      serverLabel: 'tool_router',
      serverUrl: mcpUrl,
      headers: { 'x-api-key': composioApiKey },
      requireApproval: 'never',
    }),
  ],
});
What's happening:
  • We're creating an Agent instance with a name, model (gpt-5), and clear instructions about its purpose.
  • The agent's instructions tell it that it can access Mx toolbox and help with queries, inserts, updates, authentication, and fetching database information.
  • The tools array includes a hostedMcpTool that connects to the MCP server URL we created earlier.
  • The headers object includes the Composio API key for secure authentication with the MCP server.
  • requireApproval: 'never' means the agent can execute Mx toolbox operations without asking for permission each time, making interactions smoother.
9

Start chat loop and handle conversation

// Keep conversation state across turns
const conversationSession = new OpenAIConversationsSession();

// Simple CLI
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
  prompt: 'You: ',
});

console.log('\nComposio Tool Router session created.');
console.log('\nChat started. Type your requests below.');
console.log("Commands: 'exit', 'quit', or 'q' to end\n");

try {
  const first = await run(agent, 'What can you help me with?', { session: conversationSession });
  console.log(`Assistant: ${first.finalOutput}\n`);
} catch (e) {
  console.error('Error:', e instanceof Error ? e.message : e, '\n');
}

rl.prompt();

rl.on('line', async (userInput) => {
  const text = userInput.trim();

  if (['exit', 'quit', 'q'].includes(text.toLowerCase())) {
    console.log('Goodbye!');
    rl.close();
    process.exit(0);
  }

  if (!text) {
    rl.prompt();
    return;
  }

  try {
    const result = await run(agent, text, { session: conversationSession });
    console.log(`\nAssistant: ${result.finalOutput}\n`);
  } catch (e) {
    console.error('Error:', e instanceof Error ? e.message : e, '\n');
  }

  rl.prompt();
});

rl.on('close', () => {
  console.log('\n👋 Session ended.');
  process.exit(0);
});
What's happening:
  • The program prints a session URL that you visit to authorize Mx toolbox.
  • After authorization, the chat begins.
  • Each message you type is processed by the agent using run().
  • The responses are printed to the console.
  • Typing exit, quit, or q cleanly ends the chat.

Complete Code

Here's the complete code to get you started with Mx toolbox and OpenAI Agents SDK:

import 'dotenv/config';
import { Composio } from '@composio/core';
import { OpenAIAgentsProvider } from '@composio/openai-agents';
import { Agent, hostedMcpTool, run, OpenAIConversationsSession } from '@openai/agents';
import * as readline from 'readline';

const composioApiKey = process.env.COMPOSIO_API_KEY;
const userId = process.env.USER_ID;

if (!composioApiKey) {
  throw new Error('COMPOSIO_API_KEY is not set. Create a .env file with COMPOSIO_API_KEY=your_key');
}
if (!userId) {
  throw new Error('USER_ID is not set');
}

// Initialize Composio
const composio = new Composio({
  apiKey: composioApiKey,
  provider: new OpenAIAgentsProvider(),
});

async function main() {
  // Create Tool Router session
  const session = await composio.create(userId as string, {
    toolkits: ['mx_toolbox'],
  });
  const mcpUrl = session.mcp.url;

  // Configure agent with MCP tool
  const agent = new Agent({
    name: 'Assistant',
    model: 'gpt-5',
    instructions:
      'You are a helpful assistant that can access Mx toolbox. Help users perform Mx toolbox operations through natural language.',
    tools: [
      hostedMcpTool({
        serverLabel: 'tool_router',
        serverUrl: mcpUrl,
        headers: { 'x-api-key': composioApiKey },
        requireApproval: 'never',
      }),
    ],
  });

  // Keep conversation state across turns
  const conversationSession = new OpenAIConversationsSession();

  // Simple CLI
  const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
    prompt: 'You: ',
  });

  console.log('\nComposio Tool Router session created.');
  console.log('\nChat started. Type your requests below.');
  console.log("Commands: 'exit', 'quit', or 'q' to end\n");

  try {
    const first = await run(agent, 'What can you help me with?', { session: conversationSession });
    console.log(`Assistant: ${first.finalOutput}\n`);
  } catch (e) {
    console.error('Error:', e instanceof Error ? e.message : e, '\n');
  }

  rl.prompt();

  rl.on('line', async (userInput) => {
    const text = userInput.trim();

    if (['exit', 'quit', 'q'].includes(text.toLowerCase())) {
      console.log('Goodbye!');
      rl.close();
      process.exit(0);
    }

    if (!text) {
      rl.prompt();
      return;
    }

    try {
      const result = await run(agent, text, { session: conversationSession });
      console.log(`\nAssistant: ${result.finalOutput}\n`);
    } catch (e) {
      console.error('Error:', e instanceof Error ? e.message : e, '\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

This was a starter code for integrating Mx toolbox MCP with OpenAI Agents SDK to build a functional AI agent that can interact with Mx toolbox.

Key features:

  • Hosted MCP tool integration through Composio's Tool Router
  • SQLite session persistence for conversation history
  • Simple async chat loop for interactive testing
You can extend this by adding more toolkits, implementing custom business logic, or building a web interface around the agent.
TOOLS

Supported Tools

Every Mx toolbox action and event your agent gets out of the box.

Lookup BIMI Record

Retrieves BIMI (Brand Indicators for Message Identification) record and diagnostic information for a domain.

Lookup Blacklist

Tool to perform a blacklist check on a domain or IP.

Lookup DKIM Record

Tool to retrieve DKIM (DomainKeys Identified Mail) records for a domain.

Lookup DMARC Record

Retrieves DMARC (Domain-based Message Authentication, Reporting & Conformance) records for a domain and performs validation checks.

Lookup DNS Records

Performs comprehensive DNS health check and retrieves name server records for a domain.

HTTP Lookup

Tool to perform an HTTP test on a domain.

Lookup MTA-STS Record

Tool to lookup MTA-STS record for a domain.

Lookup MX Records

Retrieves MX (Mail Exchange) records for a domain.

Ping Lookup

Performs a ping test to check network connectivity and measure round-trip time to a domain or IP address.

SMTP Lookup

Tool to perform an SMTP connectivity test on a domain.

Lookup SPF Record

Tool to retrieve SPF records for a specified domain.

Monitor Status

Retrieves the current status of all monitors configured in the MX Toolbox account.

Check Usage

Retrieve API usage statistics for DNS and network lookups.

FAQ

Frequently asked questions

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

Yes, you can. OpenAI Agents SDK 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 Mx toolbox tools.

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

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