# How to integrate Mailbluster MCP with CrewAI ```json { "title": "How to integrate Mailbluster MCP with CrewAI", "toolkit": "Mailbluster", "toolkit_slug": "mailbluster", "framework": "CrewAI", "framework_slug": "crew-ai", "url": "https://composio.dev/toolkits/mailbluster/framework/crew-ai", "markdown_url": "https://composio.dev/toolkits/mailbluster/framework/crew-ai.md", "updated_at": "2026-05-12T10:18:05.428Z" } ``` ## Introduction This guide walks you through connecting Mailbluster to CrewAI using the Composio tool router. By the end, you'll have a working Mailbluster agent that can add new lead with email and name, list all products in your catalog, get details for recent order by id through natural language commands. This guide will help you understand how to give your CrewAI agent real control over a Mailbluster account through Composio's Mailbluster MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved. ## Also integrate Mailbluster with - [OpenAI Agents SDK](https://composio.dev/toolkits/mailbluster/framework/open-ai-agents-sdk) - [Claude Agent SDK](https://composio.dev/toolkits/mailbluster/framework/claude-agents-sdk) - [Claude Code](https://composio.dev/toolkits/mailbluster/framework/claude-code) - [Claude Cowork](https://composio.dev/toolkits/mailbluster/framework/claude-cowork) - [Codex](https://composio.dev/toolkits/mailbluster/framework/codex) - [OpenClaw](https://composio.dev/toolkits/mailbluster/framework/openclaw) - [Hermes](https://composio.dev/toolkits/mailbluster/framework/hermes-agent) - [CLI](https://composio.dev/toolkits/mailbluster/framework/cli) - [Google ADK](https://composio.dev/toolkits/mailbluster/framework/google-adk) - [LangChain](https://composio.dev/toolkits/mailbluster/framework/langchain) - [Vercel AI SDK](https://composio.dev/toolkits/mailbluster/framework/ai-sdk) - [Mastra AI](https://composio.dev/toolkits/mailbluster/framework/mastra-ai) - [LlamaIndex](https://composio.dev/toolkits/mailbluster/framework/llama-index) ## TL;DR Here's what you'll learn: - Get a Composio API key and configure your Mailbluster connection - Set up CrewAI with an MCP enabled agent - Create a Tool Router session or standalone MCP server for Mailbluster - Build a conversational loop where your agent can execute Mailbluster operations ## What is CrewAI? CrewAI is a powerful framework for building multi-agent AI systems. It provides primitives for defining agents with specific roles, creating tasks, and orchestrating workflows through crews. Key features include: - Agent Roles: Define specialized agents with specific goals and backstories - Task Management: Create tasks with clear descriptions and expected outputs - Crew Orchestration: Combine agents and tasks into collaborative workflows - MCP Integration: Connect to external tools through Model Context Protocol ## What is the Mailbluster MCP server, and what's possible with it? The Mailbluster MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Mailbluster account. It provides structured and secure access to your email marketing tools and data, so your agent can perform actions like creating leads, managing products, processing orders, and listing campaign resources on your behalf. - Lead creation and management: Seamlessly add new leads to your Mailbluster campaigns with just an agent prompt, ensuring your audience list stays up to date. - Product catalog management: Let your agent create, retrieve, list, or delete products in your Mailbluster catalog, making it easy to manage what you promote via email. - Order processing and tracking: Automatically create, fetch, list, or delete orders, so you always have up-to-date insights into campaign transactions and purchases. - Custom field discovery: Easily retrieve all custom fields defined in your Mailbluster account, helping your agent personalize emails or segment audiences with precision. - Bulk resource listing: Quickly list all products or orders with advanced filtering, sorting, and pagination, empowering your agent to generate tailored campaign reports or summaries. ## Supported Tools | Tool slug | Name | Description | |---|---|---| | `MAILBLUSTER_CREATE_LEAD` | Create MailBluster Lead | Tool to create a new lead in MailBluster. Use after gathering the lead's email and optional data. | | `MAILBLUSTER_CREATE_ORDER` | Create Order | Tool to create a new order in MailBluster. | | `MAILBLUSTER_CREATE_PRODUCT` | Create Product | Tool to create a new product in MailBluster. Use when you have all product details ready to add it to your MailBluster catalog. Requires a unique product ID and name. | | `MAILBLUSTER_DELETE_LEAD` | Delete MailBluster Lead | Tool to delete a lead by lead email hash. Use after confirming the lead hash (MD5 encrypted email address). | | `MAILBLUSTER_DELETE_ORDER` | Delete Order | Tool to delete a specific order. Use after confirming the order ID to remove an order from Mailbluster. | | `MAILBLUSTER_DELETE_PRODUCT` | Delete Mailbluster Product | Tool to delete a product. Use after confirming product existence. | | `MAILBLUSTER_GET_LEAD` | Get Lead | Tool to retrieve a specific lead's information using their lead hash (MD5 encrypted email address). Use when you need to fetch lead details by their email hash. | | `MAILBLUSTER_GET_ORDER` | Get Order | Tool to retrieve details of a specific order. Use when you have the order's ID. | | `MAILBLUSTER_GET_PRODUCT` | Get Product | Tool to retrieve details of a specific product. Use when you have a valid product ID and need full product information. | | `MAILBLUSTER_LIST_FIELDS` | List Fields | Tool to list all custom fields. Use when you need to retrieve all defined custom fields after authenticating with MailBluster. | | `MAILBLUSTER_LIST_ORDERS` | List Orders | Tool to list all orders. Use when you need to retrieve orders with optional pagination, sorting, or searching after authenticating with Mailbluster. | | `MAILBLUSTER_LIST_PRODUCTS` | List Products | Tool to list all products. Use when you need to retrieve products with optional pagination, sorting, or filtering. | | `MAILBLUSTER_UPDATE_LEAD` | Update MailBluster Lead | Tool to update an existing lead's information in MailBluster. Use when you need to modify lead details, subscription status, or manage tags. | | `MAILBLUSTER_UPDATE_ORDER` | Update Order | Tool to update an existing order's customer details, currency, price, and items in MailBluster. Use when you need to modify an order. | | `MAILBLUSTER_UPDATE_PRODUCT` | MailBluster Update Product | Tool to update a product in MailBluster by its ID. Use after confirming the product ID to modify attributes. | ## Supported Triggers None listed. ## Creating MCP Server - Stand-alone vs Composio SDK The Mailbluster MCP server is an implementation of the Model Context Protocol that connects your AI agent to Mailbluster. It provides structured and secure access so your agent can perform Mailbluster 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 Before starting, make sure you have: - Python 3.9 or higher - A Composio account and API key - A Mailbluster connection authorized in Composio - An OpenAI API key for the CrewAI LLM - Basic familiarity with Python ### 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 **What's happening:** - composio connects your agent to Mailbluster via MCP - crewai provides Agent, Task, Crew, and LLM primitives - crewai-tools[mcp] includes MCP helpers - python-dotenv loads environment variables from .env ```bash pip install composio crewai crewai-tools[mcp] python-dotenv ``` ### 3. Set up environment variables Create a .env file in your project root. What's happening: - COMPOSIO_API_KEY authenticates with Composio - USER_ID scopes the session to your account - OPENAI_API_KEY lets CrewAI use your chosen OpenAI model ```bash COMPOSIO_API_KEY=your_composio_api_key_here USER_ID=your_user_id_here OPENAI_API_KEY=your_openai_api_key_here ``` ### 4. Import dependencies **What's happening:** - CrewAI classes define agents and tasks, and run the workflow - MCPServerHTTP connects the agent to an MCP endpoint - Composio will give you a short lived Mailbluster MCP URL ```python import os from composio import Composio from crewai import Agent, Task, Crew from crewai_tools import MCPServerAdapter import dotenv dotenv.load_dotenv() COMPOSIO_API_KEY = os.getenv("COMPOSIO_API_KEY") COMPOSIO_USER_ID = os.getenv("COMPOSIO_USER_ID") if not COMPOSIO_API_KEY: raise ValueError("COMPOSIO_API_KEY is not set") if not COMPOSIO_USER_ID: raise ValueError("COMPOSIO_USER_ID is not set") ``` ### 5. Create a Composio Tool Router session for Mailbluster **What's happening:** - You create a Mailbluster only session through Composio - Composio returns an MCP HTTP URL that exposes Mailbluster tools ```python composio_client = Composio(api_key=COMPOSIO_API_KEY) session = composio_client.create(user_id=COMPOSIO_USER_ID, toolkits=["mailbluster"]) url = session.mcp.url ``` ### 6. Initialize the MCP Server **What's Happening:** - Server Configuration: The code sets up connection parameters including the MCP server URL, streamable HTTP transport, and Composio API key authentication. - MCP Adapter Bridge: MCPServerAdapter acts as a context manager that converts Composio MCP tools into a CrewAI-compatible format. - Agent Setup: Creates a CrewAI Agent with a defined role (Search Assistant), goal (help with internet searches), and access to the MCP tools. - Configuration Options: The agent includes settings like verbose=False for clean output and max_iter=10 to prevent infinite loops. - Dynamic Tool Usage: Once created, the agent automatically accesses all Composio Search tools and decides when to use them based on user queries. ```python server_params = { "url": url, "transport": "streamable-http", "headers": {"x-api-key": COMPOSIO_API_KEY}, } with MCPServerAdapter(server_params) as tools: agent = Agent( role="Search Assistant", goal="Help users search the internet effectively", backstory="You are a helpful assistant with access to search tools.", tools=tools, verbose=False, max_iter=10, ) ``` ### 7. Create a CLI Chatloop and define the Crew **What's Happening:** - Interactive CLI Setup: The code creates an infinite loop that continuously prompts for user input and maintains the entire conversation history in a string variable. - Input Validation: Empty inputs are ignored to prevent processing blank messages and keep the conversation clean. - Context Building: Each user message is appended to the conversation context, which preserves the full dialogue history for better agent responses. - Dynamic Task Creation: For every user input, a new Task is created that includes both the full conversation history and the current request as context. - Crew Execution: A Crew is instantiated with the agent and task, then kicked off to process the request and generate a response. - Response Management: The agent's response is converted to a string, added to the conversation context, and displayed to the user, maintaining conversational continuity. ```python print("Chat started! Type 'exit' or 'quit' to end.\n") conversation_context = "" while True: user_input = input("You: ").strip() if user_input.lower() in ["exit", "quit", "bye"]: print("\nGoodbye!") break if not user_input: continue conversation_context += f"\nUser: {user_input}\n" print("\nAgent is thinking...\n") task = Task( description=( f"Conversation history:\n{conversation_context}\n\n" f"Current request: {user_input}" ), expected_output="A helpful response addressing the user's request", agent=agent, ) crew = Crew(agents=[agent], tasks=[task], verbose=False) result = crew.kickoff() response = str(result) conversation_context += f"Agent: {response}\n" print(f"Agent: {response}\n") ``` ## Complete Code ```python from crewai import Agent, Task, Crew, LLM from crewai_tools import MCPServerAdapter from composio import Composio from dotenv import load_dotenv import os load_dotenv() GOOGLE_API_KEY = os.getenv("GOOGLE_API_KEY") COMPOSIO_API_KEY = os.getenv("COMPOSIO_API_KEY") COMPOSIO_USER_ID = os.getenv("COMPOSIO_USER_ID") if not GOOGLE_API_KEY: raise ValueError("GOOGLE_API_KEY is not set in the environment.") if not COMPOSIO_API_KEY: raise ValueError("COMPOSIO_API_KEY is not set in the environment.") if not COMPOSIO_USER_ID: raise ValueError("COMPOSIO_USER_ID is not set in the environment.") # Initialize Composio and create a session composio = Composio(api_key=COMPOSIO_API_KEY) session = composio.create( user_id=COMPOSIO_USER_ID, toolkits=["mailbluster"], ) url = session.mcp.url # Configure LLM llm = LLM( model="gpt-5", api_key=os.getenv("OPENAI_API_KEY"), ) server_params = { "url": url, "transport": "streamable-http", "headers": {"x-api-key": COMPOSIO_API_KEY}, } with MCPServerAdapter(server_params) as tools: agent = Agent( role="Search Assistant", goal="Help users with internet searches", backstory="You are an expert assistant with access to Composio Search tools.", tools=tools, llm=llm, verbose=False, max_iter=10, ) print("Chat started! Type 'exit' or 'quit' to end.\n") conversation_context = "" while True: user_input = input("You: ").strip() if user_input.lower() in ["exit", "quit", "bye"]: print("\nGoodbye!") break if not user_input: continue conversation_context += f"\nUser: {user_input}\n" print("\nAgent is thinking...\n") task = Task( description=( f"Conversation history:\n{conversation_context}\n\n" f"Current request: {user_input}" ), expected_output="A helpful response addressing the user's request", agent=agent, ) crew = Crew(agents=[agent], tasks=[task], verbose=False) result = crew.kickoff() response = str(result) conversation_context += f"Agent: {response}\n" print(f"Agent: {response}\n") ``` ## Conclusion You now have a CrewAI agent connected to Mailbluster through Composio's Tool Router. The agent can perform Mailbluster operations through natural language commands. Next steps: - Add role-specific instructions to customize agent behavior - Plug in more toolkits for multi-app workflows - Chain tasks for complex multi-step operations ## How to build Mailbluster MCP Agent with another framework - [OpenAI Agents SDK](https://composio.dev/toolkits/mailbluster/framework/open-ai-agents-sdk) - [Claude Agent SDK](https://composio.dev/toolkits/mailbluster/framework/claude-agents-sdk) - [Claude Code](https://composio.dev/toolkits/mailbluster/framework/claude-code) - [Claude Cowork](https://composio.dev/toolkits/mailbluster/framework/claude-cowork) - [Codex](https://composio.dev/toolkits/mailbluster/framework/codex) - [OpenClaw](https://composio.dev/toolkits/mailbluster/framework/openclaw) - [Hermes](https://composio.dev/toolkits/mailbluster/framework/hermes-agent) - [CLI](https://composio.dev/toolkits/mailbluster/framework/cli) - [Google ADK](https://composio.dev/toolkits/mailbluster/framework/google-adk) - [LangChain](https://composio.dev/toolkits/mailbluster/framework/langchain) - [Vercel AI SDK](https://composio.dev/toolkits/mailbluster/framework/ai-sdk) - [Mastra AI](https://composio.dev/toolkits/mailbluster/framework/mastra-ai) - [LlamaIndex](https://composio.dev/toolkits/mailbluster/framework/llama-index) ## Related Toolkits - [Reddit](https://composio.dev/toolkits/reddit) - Reddit is a social news platform with thriving user-driven communities (subreddits). It's the go-to place for discussion, content sharing, and viral marketing. - [Facebook](https://composio.dev/toolkits/facebook) - Facebook is a social media and advertising platform for businesses and creators. It helps you connect, share, and manage content across your public Facebook Pages. - [Linkedin](https://composio.dev/toolkits/linkedin) - LinkedIn is a professional networking platform for connecting, sharing content, and engaging with business opportunities. It's the go-to place for building your professional brand and unlocking new career connections. - [Active campaign](https://composio.dev/toolkits/active_campaign) - ActiveCampaign is a marketing automation and CRM platform for managing email campaigns, sales pipelines, and customer segmentation. It helps businesses engage customers and drive growth through smart automation and targeted outreach. - [ActiveTrail](https://composio.dev/toolkits/active_trail) - ActiveTrail is a user-friendly email marketing and automation platform. It helps you reach subscribers and automate campaigns with ease. - [Ahrefs](https://composio.dev/toolkits/ahrefs) - Ahrefs is an SEO and marketing platform for site audits, keyword research, and competitor insights. It helps you improve search rankings and drive organic traffic. - [Amcards](https://composio.dev/toolkits/amcards) - AMCards lets you create and mail personalized greeting cards online. Build stronger customer relationships with easy, automated card campaigns. - [Beamer](https://composio.dev/toolkits/beamer) - Beamer is a news and changelog platform for in-app announcements and feature updates. It helps companies boost user engagement by sharing news where users are most active. - [Benchmark email](https://composio.dev/toolkits/benchmark_email) - Benchmark Email is a platform for creating, sending, and tracking email campaigns. It's built to help you engage audiences and analyze results—all in one place. - [Bigmailer](https://composio.dev/toolkits/bigmailer) - BigMailer is an email marketing platform for managing multiple brands with white-labeling and automation. It helps teams streamline campaigns and simplify integration with Amazon SES. - [Brandfetch](https://composio.dev/toolkits/brandfetch) - Brandfetch is an API that delivers company logos, colors, and visual branding assets. It helps marketers and developers keep brand visuals consistent everywhere. - [Brevo](https://composio.dev/toolkits/brevo) - Brevo is an all-in-one email and SMS marketing platform for transactional messaging, automation, and CRM. It helps businesses engage customers and streamline communications through powerful campaign tools. - [Campayn](https://composio.dev/toolkits/campayn) - Campayn is an email marketing platform for creating, sending, and managing campaigns. It helps businesses engage contacts and grow audiences with easy-to-use tools. - [Cardly](https://composio.dev/toolkits/cardly) - Cardly is a platform for creating and sending personalized direct mail to customers. It helps businesses break through the digital clutter by getting real engagement via physical mailboxes. - [ClickSend](https://composio.dev/toolkits/clicksend) - ClickSend is a cloud-based SMS and email marketing platform for businesses. It streamlines communication by enabling quick message delivery and contact management. - [Crustdata](https://composio.dev/toolkits/crustdata) - CrustData is an AI-powered data intelligence platform for real-time company and people data. It helps B2B sales teams, AI SDRs, and investors react to live business signals. - [Curated](https://composio.dev/toolkits/curated) - Curated is a platform for collecting, curating, and publishing newsletters. It streamlines content aggregation and distribution for creators and teams. - [Customerio](https://composio.dev/toolkits/customerio) - Customer.io is a customer engagement platform for targeted messaging across email, SMS, and push. Easily automate, segment, and track communications with your audience. - [Cutt ly](https://composio.dev/toolkits/cutt_ly) - Cutt.ly is a URL shortening service for managing and analyzing links. Streamline your workflows with quick, trackable, and branded short URLs. - [Demio](https://composio.dev/toolkits/demio) - Demio is webinar software built for marketers, offering both live and automated sessions with interactive features. It helps teams engage audiences and optimize lead generation through detailed analytics. ## Frequently Asked Questions ### What are the differences in Tool Router MCP and Mailbluster MCP? With a standalone Mailbluster MCP server, the agents and LLMs can only access a fixed set of Mailbluster tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Mailbluster and many other apps based on the task at hand, all through a single MCP endpoint. ### Can I use Tool Router MCP with CrewAI? Yes, you can. CrewAI 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 Mailbluster tools. ### Can I manage the permissions and scopes for Mailbluster while using Tool Router? Yes, absolutely. You can configure which Mailbluster 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 Mailbluster data and credentials are handled as safely as possible. --- [See all toolkits](https://composio.dev/toolkits) · [Composio docs](https://docs.composio.dev/llms.txt)