How to integrate Resend MCP with Autogen

Trusted by
AWS
Glean
Zoom
Airtable

30 min · no commitment · see it on your stack

Resend logo
AutoGen logo
divider

Introduction

This guide walks you through connecting Resend to AutoGen using the Composio tool router. By the end, you'll have a working Resend agent that can create a new contact for your newsletter, list all domains connected to your account, cancel a scheduled marketing email through natural language commands.

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

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

Also integrate Resend with

TL;DR

Here's what you'll learn:
  • Get and set up your OpenAI and Composio API keys
  • Install the required dependencies for Autogen and Composio
  • Initialize Composio and create a Tool Router session for Resend
  • Wire that MCP URL into Autogen using McpWorkbench and StreamableHttpServerParams
  • Configure an Autogen AssistantAgent that can call Resend tools
  • Run a live chat loop where you ask the agent to perform Resend operations

What is AutoGen?

Autogen is a framework for building multi-agent conversational AI systems from Microsoft. It enables you to create agents that can collaborate, use tools, and maintain complex workflows.

Key features include:

  • Multi-Agent Systems: Build collaborative agent workflows
  • MCP Workbench: Native support for Model Context Protocol tools
  • Streaming HTTP: Connect to external services through streamable HTTP
  • AssistantAgent: Pre-built agent class for tool-using assistants

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

The Resend MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Resend account. It provides structured and secure access to your email sending and contact management capabilities, so your agent can perform actions like sending emails, managing audiences, creating domains, and handling contacts on your behalf.

  • Automated email delivery and scheduling: Ask your agent to send emails instantly or schedule them for later, and even cancel scheduled messages if needed.
  • Audience and contact management: Let your agent create, list, or delete audiences and individual contacts, keeping your recipient lists organized without manual effort.
  • Domain administration: Easily have your agent set up, list, or remove email sending domains, streamlining onboarding or maintenance for your email infrastructure.
  • Seamless recipient segmentation: Direct your agent to group contacts into audiences for targeted campaigns or communications, improving personalization and reach.
  • Bulk operations and cleanups: Enable your agent to quickly list, update, or delete multiple contacts, audiences, or domains to maintain a tidy and up-to-date email system.

Supported Tools & Triggers

Tools
Add Contact To SegmentAdd an existing contact to a segment in Resend.
Cancel EmailCancel a scheduled email.
Create API KeyCreate a new API key to authenticate communications with Resend.
Create AudienceCreate a list of contacts.
Create ContactCreate a contact in Resend.
Create Contact PropertyTool to create a new contact property in Resend.
Create Contact V2Tool to create a new contact in Resend.
Create DomainCreate a domain through the Resend Email API.
Create TemplateTool to create a new email template in Resend.
Create TopicTool to create a new topic to segment your audience.
Create WebhookTool to create a webhook to receive real-time notifications about email events.
Delete API KeyRemove an existing API key from Resend.
Delete AudienceRemove an existing audience.
Delete ContactDelete a contact in Resend.
Delete Contact By IDTool to remove an existing contact by its ID.
Delete Contact PropertyRemove an existing contact property from Resend.
Delete DomainDelete a domain through the Resend Email API.
Delete SegmentRemove an existing segment.
Delete TemplateRemove an existing template.
Delete TopicTool to remove an existing topic in Resend.
Delete WebhookRemove an existing webhook.
Duplicate TemplateDuplicate an existing template through the Resend Email API.
Get ContactTool to retrieve a single contact from Resend by ID or email.
Get Contact PropertyTool to retrieve a single contact property from Resend.
Get Email AttachmentRetrieve a single attachment from a sent email.
Get SegmentRetrieve a single segment by its ID.
Get TemplateRetrieve a single template by ID or alias from Resend.
Get TopicTool to retrieve a single topic by its ID in Resend.
Get WebhookRetrieve a single webhook for the authenticated user.
List All ContactsTool to retrieve a list of all contacts from Resend.
List API KeysTool to retrieve a list of API keys for the authenticated user.
List AudiencesList all audiences.
List BroadcastsTool to retrieve a list of broadcasts.
List Contact PropertiesTool to retrieve a list of contact properties from Resend.
List ContactsList contacts in Resend.
List Contact SegmentsRetrieve a list of segments that a contact is part of.
List Contact TopicsRetrieve a list of topic subscriptions for a contact in Resend.
List DomainsList all domains.
List Email AttachmentsTool to retrieve a list of attachments from a sent email.
List EmailsTool to retrieve a list of emails sent by your team.
List Received EmailsTool to retrieve a list of received emails for the authenticated user.
List SegmentsTool to retrieve a list of segments from Resend.
List TemplatesTool to retrieve a list of templates from Resend.
List TopicsTool to retrieve a list of topics for the authenticated user.
List WebhooksRetrieve a list of webhooks for the authenticated user.
Publish TemplatePublish a template through the Resend Email API.
Remove Contact From SegmentRemove an existing contact from a segment.
Retrieve AudienceRetrieve a single audience.
Retrieve ContactRetrieve a contact in Resend.
Retrieve DomainRetrieve a single domain.
Retrieve EmailRetrieve a single email.
Send Batch EmailsTrigger up to 100 batch emails at once.
Send EmailSend an email using Resend.
Update BroadcastUpdate an existing broadcast in Resend.
Update ContactTool to update an existing contact in Resend by ID or email.
Update Contact PropertyUpdate an existing contact property in Resend.
Update DomainUpdate an existing domain.
Update EmailUpdate a scheduled email.
Update TemplateTool to update an existing email template in Resend.
Update TopicTool to update an existing topic in Resend.
Update WebhookTool to update an existing webhook configuration.
Verify DomainVerify a domain through the Resend Email API.

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

Prerequisites

You will need:

  • A Composio API key
  • An OpenAI API key (used by Autogen's OpenAIChatCompletionClient)
  • A Resend account you can connect to Composio
  • Some basic familiarity with Autogen and Python async

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

bash
pip install composio python-dotenv
pip install autogen-agentchat autogen-ext-openai autogen-ext-tools

Install Composio, Autogen extensions, and dotenv.

What's happening:

  • composio connects your agent to Resend via MCP
  • autogen-agentchat provides the AssistantAgent class
  • autogen-ext-openai provides the OpenAI model client
  • autogen-ext-tools provides MCP workbench support

Set up environment variables

bash
COMPOSIO_API_KEY=your-composio-api-key
OPENAI_API_KEY=your-openai-api-key
USER_ID=your-user-identifier@example.com

Create a .env file in your project folder.

What's happening:

  • COMPOSIO_API_KEY is required to talk to Composio
  • OPENAI_API_KEY is used by Autogen's OpenAI client
  • USER_ID is how Composio identifies which user's Resend connections to use

Import dependencies and create Tool Router session

python
import asyncio
import os
from dotenv import load_dotenv
from composio import Composio

from autogen_agentchat.agents import AssistantAgent
from autogen_ext.models.openai import OpenAIChatCompletionClient
from autogen_ext.tools.mcp import McpWorkbench, StreamableHttpServerParams

load_dotenv()

async def main():
    # Initialize Composio and create a Resend session
    composio = Composio(api_key=os.getenv("COMPOSIO_API_KEY"))
    session = composio.create(
        user_id=os.getenv("USER_ID"),
        toolkits=["resend"]
    )
    url = session.mcp.url
What's happening:
  • load_dotenv() reads your .env file
  • Composio(api_key=...) initializes the SDK
  • create(...) creates a Tool Router session that exposes Resend tools
  • session.mcp.url is the MCP endpoint that Autogen will connect to

Configure MCP parameters for Autogen

python
# Configure MCP server parameters for Streamable HTTP
server_params = StreamableHttpServerParams(
    url=url,
    timeout=30.0,
    sse_read_timeout=300.0,
    terminate_on_close=True,
    headers={"x-api-key": os.getenv("COMPOSIO_API_KEY")}
)

Autogen expects parameters describing how to talk to the MCP server. That is what StreamableHttpServerParams is for.

What's happening:

  • url points to the Tool Router MCP endpoint from Composio
  • timeout is the HTTP timeout for requests
  • sse_read_timeout controls how long to wait when streaming responses
  • terminate_on_close=True cleans up the MCP server process when the workbench is closed

Create the model client and agent

python
# Create model client
model_client = OpenAIChatCompletionClient(
    model="gpt-5",
    api_key=os.getenv("OPENAI_API_KEY")
)

# Use McpWorkbench as context manager
async with McpWorkbench(server_params) as workbench:
    # Create Resend assistant agent with MCP tools
    agent = AssistantAgent(
        name="resend_assistant",
        description="An AI assistant that helps with Resend operations.",
        model_client=model_client,
        workbench=workbench,
        model_client_stream=True,
        max_tool_iterations=10
    )

What's happening:

  • OpenAIChatCompletionClient wraps the OpenAI model for Autogen
  • McpWorkbench connects the agent to the MCP tools
  • AssistantAgent is configured with the Resend tools from the workbench

Run the interactive chat loop

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

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

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

    if not user_input:
        continue

    print("\nAgent is thinking...\n")

    # Run the agent with streaming
    try:
        response_text = ""
        async for message in agent.run_stream(task=user_input):
            if hasattr(message, "content") and message.content:
                response_text = message.content

        # Print the final response
        if response_text:
            print(f"Agent: {response_text}\n")
        else:
            print("Agent: I encountered an issue processing your request.\n")

    except Exception as e:
        print(f"Agent: Sorry, I encountered an error: {str(e)}\n")
What's happening:
  • The script prompts you in a loop with You:
  • Autogen passes your input to the model, which decides which Resend tools to call via MCP
  • agent.run_stream(...) yields streaming messages as the agent thinks and calls tools
  • Typing exit, quit, or bye ends the loop

Complete Code

Here's the complete code to get you started with Resend and AutoGen:

python
import asyncio
import os
from dotenv import load_dotenv
from composio import Composio

from autogen_agentchat.agents import AssistantAgent
from autogen_ext.models.openai import OpenAIChatCompletionClient
from autogen_ext.tools.mcp import McpWorkbench, StreamableHttpServerParams

load_dotenv()

async def main():
    # Initialize Composio and create a Resend session
    composio = Composio(api_key=os.getenv("COMPOSIO_API_KEY"))
    session = composio.create(
        user_id=os.getenv("USER_ID"),
        toolkits=["resend"]
    )
    url = session.mcp.url

    # Configure MCP server parameters for Streamable HTTP
    server_params = StreamableHttpServerParams(
        url=url,
        timeout=30.0,
        sse_read_timeout=300.0,
        terminate_on_close=True,
        headers={"x-api-key": os.getenv("COMPOSIO_API_KEY")}
    )

    # Create model client
    model_client = OpenAIChatCompletionClient(
        model="gpt-5",
        api_key=os.getenv("OPENAI_API_KEY")
    )

    # Use McpWorkbench as context manager
    async with McpWorkbench(server_params) as workbench:
        # Create Resend assistant agent with MCP tools
        agent = AssistantAgent(
            name="resend_assistant",
            description="An AI assistant that helps with Resend operations.",
            model_client=model_client,
            workbench=workbench,
            model_client_stream=True,
            max_tool_iterations=10
        )

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

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

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

            if not user_input:
                continue

            print("\nAgent is thinking...\n")

            # Run the agent with streaming
            try:
                response_text = ""
                async for message in agent.run_stream(task=user_input):
                    if hasattr(message, 'content') and message.content:
                        response_text = message.content

                # Print the final response
                if response_text:
                    print(f"Agent: {response_text}\n")
                else:
                    print("Agent: I encountered an issue processing your request.\n")

            except Exception as e:
                print(f"Agent: Sorry, I encountered an error: {str(e)}\n")

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

Conclusion

You now have an Autogen assistant wired into Resend through Composio's Tool Router and MCP. From here you can:
  • Add more toolkits to the toolkits list, for example notion or hubspot
  • Refine the agent description to point it at specific workflows
  • Wrap this script behind a UI, Slack bot, or internal tool
Once the pattern is clear for Resend, you can reuse the same structure for other MCP-enabled apps with minimal code changes.

How to build Resend MCP Agent with another framework

FAQ

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

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

Can I use Tool Router MCP with Autogen?

Yes, you can. Autogen 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 Resend tools.

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

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

Used by agents from

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