# How to integrate Enginemailer MCP with Mastra AI ```json { "title": "How to integrate Enginemailer MCP with Mastra AI", "toolkit": "Enginemailer", "toolkit_slug": "enginemailer", "framework": "Mastra AI", "framework_slug": "mastra-ai", "url": "https://composio.dev/toolkits/enginemailer/framework/mastra-ai", "markdown_url": "https://composio.dev/toolkits/enginemailer/framework/mastra-ai.md", "updated_at": "2026-05-12T10:10:24.662Z" } ``` ## Introduction This guide walks you through connecting Enginemailer to Mastra AI using the Composio tool router. By the end, you'll have a working Enginemailer agent that can add new subscriber to newsletter list, pause tomorrow's scheduled marketing campaign, export email delivery report from last week through natural language commands. This guide will help you understand how to give your Mastra AI agent real control over a Enginemailer account through Composio's Enginemailer MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved. ## Also integrate Enginemailer with - [OpenAI Agents SDK](https://composio.dev/toolkits/enginemailer/framework/open-ai-agents-sdk) - [Claude Agent SDK](https://composio.dev/toolkits/enginemailer/framework/claude-agents-sdk) - [Claude Code](https://composio.dev/toolkits/enginemailer/framework/claude-code) - [Claude Cowork](https://composio.dev/toolkits/enginemailer/framework/claude-cowork) - [Codex](https://composio.dev/toolkits/enginemailer/framework/codex) - [OpenClaw](https://composio.dev/toolkits/enginemailer/framework/openclaw) - [Hermes](https://composio.dev/toolkits/enginemailer/framework/hermes-agent) - [CLI](https://composio.dev/toolkits/enginemailer/framework/cli) - [Google ADK](https://composio.dev/toolkits/enginemailer/framework/google-adk) - [LangChain](https://composio.dev/toolkits/enginemailer/framework/langchain) - [Vercel AI SDK](https://composio.dev/toolkits/enginemailer/framework/ai-sdk) - [LlamaIndex](https://composio.dev/toolkits/enginemailer/framework/llama-index) - [CrewAI](https://composio.dev/toolkits/enginemailer/framework/crew-ai) ## TL;DR Here's what you'll learn: - Set up your environment so Mastra, OpenAI, and Composio work together - Create a Tool Router session in Composio that exposes Enginemailer tools - Connect Mastra's MCP client to the Composio generated MCP URL - Fetch Enginemailer tool definitions and attach them as a toolset - Build a Mastra agent that can reason, call tools, and return structured results - Run an interactive CLI where you can chat with your Enginemailer agent ## What is Mastra AI? Mastra AI is a TypeScript framework for building AI agents with tool support. It provides a clean API for creating agents that can use external services through MCP. Key features include: - MCP Client: Built-in support for Model Context Protocol servers - Toolsets: Organize tools into logical groups - Step Callbacks: Monitor and debug agent execution - OpenAI Integration: Works with OpenAI models via @ai-sdk/openai ## What is the Enginemailer MCP server, and what's possible with it? The Enginemailer MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Enginemailer account. It provides structured and secure access to your email marketing platform, so your agent can perform actions like creating campaigns, managing subscriber lists, exporting reports, and sending personalized email campaigns on your behalf. - Campaign creation and scheduling: Direct your agent to set up new email campaigns, configure content, and schedule delivery to your audience. - Subscriber management: Have your agent add new subscribers to your lists, including custom fields and segmentation for targeted outreach. - Instant campaign delivery and controls: Command your agent to send campaigns immediately or pause scheduled campaigns for last-minute adjustments. - Campaign monitoring and reporting: Let your agent export detailed email campaign reports as CSV files and check the status of ongoing exports. - Audience segmentation and subcategory retrieval: Guide your agent to fetch subcategories and organize recipients for more personalized and effective campaigns. ## Supported Tools | Tool slug | Name | Description | |---|---|---| | `ENGINEMAILER_ACTIVATE_SUBSCRIBER` | Activate Subscriber | Tool to activate an inactive subscriber in EngineMailer. Use when you need to reactivate a subscriber that was previously deactivated either through the API or manually. | | `ENGINEMAILER_ADD_UPDATE_SUBSCRIBER` | Add or Update Subscriber | Tool to add or update a subscriber with custom fields via N8N integration. Use when you need to create a new subscriber or update an existing one in the EngineMailer system. | | `ENGINEMAILER_BATCH_UPDATE_STATUS` | Check Batch Update Status | Tool to check the status of a batch subscriber update operation. Use when you need to verify if a batch update job has completed or is still processing. | | `ENGINEMAILER_BATCH_UPDATE_SUBSCRIBERS` | Batch Update Subscribers | Tool to add or update multiple subscribers with custom fields in a single batch operation. Use when you need to create or update multiple subscribers efficiently. Subscribers that fail validation are removed from processing automatically. | | `ENGINEMAILER_CHECK_EXPORT_STATUS_V2` | Check Export Status V2 | Tool to check status of a previously requested CSV report export. Use after initiating an export to poll for completion. Large exports may take significant time; poll repeatedly until status indicates readiness before consuming the export data. | | `ENGINEMAILER_CONNECT` | Test API Connection | Tool to test API connection and verify authentication. Use when you need to validate API credentials or check connectivity. | | `ENGINEMAILER_CREATE_CAMPAIGN` | Create Campaign | Tool to create a new email campaign. Use when you need to configure and schedule a campaign before sending. Set trackOpens and trackClicks at creation; these flags cannot retroactively affect already-delivered messages. | | `ENGINEMAILER_DELETE_CAMPAIGN` | Delete Campaign | Tool to delete an undelivered email campaign. Use when you need to remove a campaign that has not been sent yet. | | `ENGINEMAILER_DELETE_RECIPIENT_LIST` | Delete Recipient List | Tool to delete an existing recipient list from a targeted campaign. Use when you need to remove a specific recipient list from a campaign. | | `ENGINEMAILER_DELETE_SUBSCRIBER` | Delete Subscriber | Tool to remove a subscriber from the system by email address. Use when you need to permanently delete a subscriber's record. | | `ENGINEMAILER_EXPORT_CSV_REPORT_V2` | Export CSV Report V2 | Tool to export a transactional email report as CSV. Initiates an async export within a specific date range (max past 60 days); check readiness via ENGINEMAILER_CHECK_EXPORT_STATUS_V2 before using the export. | | `ENGINEMAILER_FIND_SUBSCRIBER` | Find Subscriber | Tool to find a subscriber by email address via N8N integration. Use when you need to search for and retrieve subscriber information from the EngineMailer system. | | `ENGINEMAILER_GET_GETCUSTOMFIELD` | Get Custom Field List | Tool to retrieve the list of custom fields configured for subscribers. Use when you need to discover available custom fields for subscriber management. | | `ENGINEMAILER_GET_LISTCAMPAIGN` | Get List Campaign | Tool to get a list of undelivered campaigns. Use when you need to fetch campaigns awaiting delivery. | | `ENGINEMAILER_GET_NEW_SUBSCRIBERS` | Get New Subscribers | Tool to retrieve new subscribers with optional filtering by source, form, page, or popup. Use when you need to fetch recently added subscribers for synchronization or reporting workflows. | | `ENGINEMAILER_GET_SUBCATEGORY` | Get Subcategories | Tool to retrieve subcategories for a given category. Use when you need to list or choose subcategories after selecting a category. | | `ENGINEMAILER_GET_SUBSCRIBER` | Get Subscriber | Tool to retrieve subscriber information by email address. Use when you need to fetch details about a specific subscriber including their custom fields. | | `ENGINEMAILER_GET_SUBSCRIBER_AUTORESPONDER_COMPLETED` | Get Subscriber Autoresponder Completed | Tool to retrieve subscribers who completed autoresponders with optional filtering by autoresponder ID. Use when you need to fetch completion events for autoresponders, optionally filtered by specific autoresponder or polling for new events since a timestamp. | | `ENGINEMAILER_GET_SUBSCRIBER_AUTORESPONDER_TRIGGERED` | Get Subscriber Autoresponder Triggered | Tool to retrieve subscribers who triggered autoresponders with optional filtering by autoresponder ID. Use when you need to fetch trigger events for autoresponders, optionally filtered by specific autoresponder or polling for new events since a timestamp. | | `ENGINEMAILER_GET_SUBSCRIBERS_DELETED` | Get Deleted Subscribers | Tool to retrieve deleted subscribers since last polling date. Use when you need to track or sync subscribers who have been removed from the system. | | `ENGINEMAILER_GET_SUBSCRIBERS_MODIFIED` | Get Subscribers Modified | Tool to retrieve modified subscribers since last polling date with optional limit. Use when you need to fetch recently modified subscribers for synchronization or polling workflows. | | `ENGINEMAILER_GET_SUBSCRIBERS_TAGGED` | Get Subscribers Tagged | Tool to retrieve subscribers who were tagged with optional filtering by subcategory. Use when you need to fetch tagged subscribers for synchronization or reporting workflows. | | `ENGINEMAILER_GET_SUBSCRIBERS_UNTAGGED` | Get Untagged Subscribers | Tool to retrieve subscribers who were untagged from subcategories. Use when you need to track or sync subscribers who have had tags removed, with optional filtering by subcategory and polling date. | | `ENGINEMAILER_GET_UNSUBSCRIBE` | Get Unsubscribe Events | Tool to retrieve unsubscribe events with optional filtering by campaign or autoresponder. Use when you need to fetch unsubscribe data for reporting, synchronization, or compliance workflows. | | `ENGINEMAILER_INSERT_SUBSCRIBER` | Insert Subscriber | Tool to add a new subscriber with optional custom fields. Use when registering a user to a specific mailing list after verifying their email. | | `ENGINEMAILER_LIST_AUTORESPONDERS` | List Autoresponders | Tool to retrieve a list of all autoresponders. Use when you need to fetch available autoresponders configured in the system. | | `ENGINEMAILER_LIST_CAMPAIGNS` | List Campaigns | Tool to retrieve a list of all campaigns. Use when you need to fetch all campaigns from the system. | | `ENGINEMAILER_LIST_FORMS` | List Forms | Tool to retrieve a list of available forms in Enginemailer. Use when you need to discover forms for n8n integration or workflow configuration. | | `ENGINEMAILER_LIST_PAGES` | List Pages | Tool to retrieve a list of all pages. Use when you need to fetch available pages. | | `ENGINEMAILER_LIST_POPUPS` | List Popups | Tool to retrieve a list of popups from Enginemailer. Use when you need to fetch available popups for n8n workflows. | | `ENGINEMAILER_LIST_TEMPLATES` | List Templates | Tool to retrieve a list of all email templates. Use when you need to fetch available email templates for campaigns. | | `ENGINEMAILER_PAUSE_CAMPAIGN` | Pause Campaign | Tool to pause a scheduled email campaign. Use when you need to halt a campaign before sending to apply updates or adjust schedule. | | `ENGINEMAILER_POST_UPDATECATEGORY` | Create/Update Category | Tool to create or update a category for subscriber segmentation. Use when organizing subscribers by common interests for targeted email marketing. | | `ENGINEMAILER_POST_UPDATE_SUBSCRIBER` | Update Subscriber | Tool to update data for an existing subscriber in EngineMailer. Use when you need to modify subscriber information such as custom fields or subcategory assignments. | | `ENGINEMAILER_SEND_CAMPAIGN` | Send Campaign | Tool to send an email campaign immediately. Use when the campaign exists, has at least one recipient, and is not scheduled or already delivered. E.g., 'Send campaign 123 now'. | | `ENGINEMAILER_TAG_TO_SUBCATEGORY` | Tag Subscriber to Subcategory | Tool to tag a subscriber to a specific subcategory via N8N API endpoint. Use when you need to categorize or organize subscribers by assigning them to a subcategory. | | `ENGINEMAILER_UNSUBSCRIBE` | Unsubscribe (N8N) | Tool to unsubscribe a subscriber via N8N API endpoint. Use when you need to remove a subscriber from the mailing list using the N8N integration endpoint. | | `ENGINEMAILER_UNSUBSCRIBE_SUBSCRIBER` | Unsubscribe Subscriber | Tool to unsubscribe a subscriber from the email list. Use when a user requests to be removed from the mailing list or to comply with unsubscribe requests. | ## Supported Triggers None listed. ## Creating MCP Server - Stand-alone vs Composio SDK The Enginemailer MCP server is an implementation of the Model Context Protocol that connects your AI agent to Enginemailer. It provides structured and secure access so your agent can perform Enginemailer 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: - Node.js 18 or higher - A Composio account with an active API key - An OpenAI API key - Basic familiarity with TypeScript ### 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 need credits or a connected billing setup to use the models. - Store the key somewhere safe. Composio API Key - Log in to the [Composio dashboard](https://dashboard.composio.dev?utm_source=toolkits&utm_medium=framework_docs). - Go to Settings and copy your API key. - This key lets your Mastra agent talk to Composio and reach Enginemailer through MCP. ### 2. Install dependencies Install the required packages. What's happening: - @composio/core is the Composio SDK for creating MCP sessions - @mastra/core provides the Agent class - @mastra/mcp is Mastra's MCP client - @ai-sdk/openai is the model wrapper for OpenAI - dotenv loads environment variables from .env ```bash npm install @composio/core @mastra/core @mastra/mcp @ai-sdk/openai 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 - COMPOSIO_USER_ID tells Composio which user this session belongs to - OPENAI_API_KEY lets the Mastra agent call OpenAI models ```bash COMPOSIO_API_KEY=your_composio_api_key_here COMPOSIO_USER_ID=your_user_id_here OPENAI_API_KEY=your_openai_api_key_here ``` ### 4. Import libraries and validate environment What's happening: - dotenv/config auto loads your .env so process.env.* is available - openai gives you a Mastra compatible model wrapper - Agent is the Mastra agent that will call tools and produce answers - MCPClient connects Mastra to your Composio MCP server - Composio is used to create a Tool Router session ```typescript import "dotenv/config"; import { openai } from "@ai-sdk/openai"; import { Agent } from "@mastra/core/agent"; import { MCPClient } from "@mastra/mcp"; import { Composio } from "@composio/core"; import * as readline from "readline"; import type { AiMessageType } from "@mastra/core/agent"; const openaiAPIKey = process.env.OPENAI_API_KEY; const composioAPIKey = process.env.COMPOSIO_API_KEY; const composioUserID = process.env.COMPOSIO_USER_ID; if (!openaiAPIKey) throw new Error("OPENAI_API_KEY is not set"); if (!composioAPIKey) throw new Error("COMPOSIO_API_KEY is not set"); if (!composioUserID) throw new Error("COMPOSIO_USER_ID is not set"); const composio = new Composio({ apiKey: composioAPIKey as string, }); ``` ### 5. Create a Tool Router session for Enginemailer What's happening: - create spins up a short-lived MCP HTTP endpoint for this user - The toolkits array contains "enginemailer" for Enginemailer access - session.mcp.url is the MCP URL that Mastra's MCPClient will connect to ```typescript async function main() { const session = await composio.create( composioUserID as string, { toolkits: ["enginemailer"], }, ); const composioMCPUrl = session.mcp.url; console.log("Enginemailer MCP URL:", composioMCPUrl); ``` ### 6. Configure Mastra MCP client and fetch tools What's happening: - MCPClient takes an id for this client and a list of MCP servers - The headers property includes the x-api-key for authentication - getTools fetches the tool definitions exposed by the Enginemailer toolkit ```typescript const mcpClient = new MCPClient({ id: composioUserID as string, servers: { nasdaq: { url: new URL(composioMCPUrl), requestInit: { headers: session.mcp.headers, }, }, }, timeout: 30_000, }); console.log("Fetching MCP tools from Composio..."); const composioTools = await mcpClient.getTools(); console.log("Number of tools:", Object.keys(composioTools).length); ``` ### 7. Create the Mastra agent What's happening: - Agent is the core Mastra agent - name is just an identifier for logging and debugging - instructions guide the agent to use tools instead of only answering in natural language - model uses openai("gpt-5") to configure the underlying LLM ```typescript const agent = new Agent({ name: "enginemailer-mastra-agent", instructions: "You are an AI agent with Enginemailer tools via Composio.", model: "openai/gpt-5", }); ``` ### 8. Set up interactive chat interface What's happening: - messages keeps the full conversation history in Mastra's expected format - agent.generate runs the agent with conversation history and Enginemailer toolsets - maxSteps limits how many tool calls the agent can take in a single run - onStepFinish is a hook that prints intermediate steps for debugging ```typescript let messages: AiMessageType[] = []; console.log("Chat started! Type 'exit' or 'quit' to end.\n"); const rl = readline.createInterface({ input: process.stdin, output: process.stdout, prompt: "> ", }); 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; } messages.push({ id: crypto.randomUUID(), role: "user", content: trimmedInput, }); console.log("\nAgent is thinking...\n"); try { const response = await agent.generate(messages, { toolsets: { enginemailer: composioTools, }, maxSteps: 8, }); const { text } = response; if (text && text.trim().length > 0) { console.log(`Agent: ${text}\n`); messages.push({ id: crypto.randomUUID(), role: "assistant", content: text, }); } } catch (error) { console.error("\nError:", error); } rl.prompt(); }); rl.on("close", async () => { console.log("\nSession ended."); await mcpClient.disconnect(); process.exit(0); }); } main().catch((err) => { console.error("Fatal error:", err); process.exit(1); }); ``` ## Complete Code ```typescript import "dotenv/config"; import { openai } from "@ai-sdk/openai"; import { Agent } from "@mastra/core/agent"; import { MCPClient } from "@mastra/mcp"; import { Composio } from "@composio/core"; import * as readline from "readline"; import type { AiMessageType } from "@mastra/core/agent"; const openaiAPIKey = process.env.OPENAI_API_KEY; const composioAPIKey = process.env.COMPOSIO_API_KEY; const composioUserID = process.env.COMPOSIO_USER_ID; if (!openaiAPIKey) throw new Error("OPENAI_API_KEY is not set"); if (!composioAPIKey) throw new Error("COMPOSIO_API_KEY is not set"); if (!composioUserID) throw new Error("COMPOSIO_USER_ID is not set"); const composio = new Composio({ apiKey: composioAPIKey as string }); async function main() { const session = await composio.create(composioUserID as string, { toolkits: ["enginemailer"], }); const composioMCPUrl = session.mcp.url; const mcpClient = new MCPClient({ id: composioUserID as string, servers: { enginemailer: { url: new URL(composioMCPUrl), requestInit: { headers: session.mcp.headers, }, }, }, timeout: 30_000, }); const composioTools = await mcpClient.getTools(); const agent = new Agent({ name: "enginemailer-mastra-agent", instructions: "You are an AI agent with Enginemailer tools via Composio.", model: "openai/gpt-5", }); let messages: AiMessageType[] = []; const rl = readline.createInterface({ input: process.stdin, output: process.stdout, prompt: "> ", }); rl.prompt(); rl.on("line", async (input: string) => { const trimmed = input.trim(); if (["exit", "quit"].includes(trimmed.toLowerCase())) { rl.close(); return; } messages.push({ id: crypto.randomUUID(), role: "user", content: trimmed }); const { text } = await agent.generate(messages, { toolsets: { enginemailer: composioTools }, maxSteps: 8, }); if (text) { console.log(`Agent: ${text}\n`); messages.push({ id: crypto.randomUUID(), role: "assistant", content: text }); } rl.prompt(); }); rl.on("close", async () => { await mcpClient.disconnect(); process.exit(0); }); } main(); ``` ## Conclusion You've built a Mastra AI agent that can interact with Enginemailer through Composio's Tool Router. You can extend this further by: - Adding other toolkits like Gmail, Slack, or GitHub - Building a web-based chat interface around this agent - Using multiple MCP endpoints to enable cross-app workflows ## How to build Enginemailer MCP Agent with another framework - [OpenAI Agents SDK](https://composio.dev/toolkits/enginemailer/framework/open-ai-agents-sdk) - [Claude Agent SDK](https://composio.dev/toolkits/enginemailer/framework/claude-agents-sdk) - [Claude Code](https://composio.dev/toolkits/enginemailer/framework/claude-code) - [Claude Cowork](https://composio.dev/toolkits/enginemailer/framework/claude-cowork) - [Codex](https://composio.dev/toolkits/enginemailer/framework/codex) - [OpenClaw](https://composio.dev/toolkits/enginemailer/framework/openclaw) - [Hermes](https://composio.dev/toolkits/enginemailer/framework/hermes-agent) - [CLI](https://composio.dev/toolkits/enginemailer/framework/cli) - [Google ADK](https://composio.dev/toolkits/enginemailer/framework/google-adk) - [LangChain](https://composio.dev/toolkits/enginemailer/framework/langchain) - [Vercel AI SDK](https://composio.dev/toolkits/enginemailer/framework/ai-sdk) - [LlamaIndex](https://composio.dev/toolkits/enginemailer/framework/llama-index) - [CrewAI](https://composio.dev/toolkits/enginemailer/framework/crew-ai) ## 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 Enginemailer MCP? With a standalone Enginemailer MCP server, the agents and LLMs can only access a fixed set of Enginemailer tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Enginemailer and many other apps based on the task at hand, all through a single MCP endpoint. ### Can I use Tool Router MCP with Mastra AI? Yes, you can. Mastra AI 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 Enginemailer tools. ### Can I manage the permissions and scopes for Enginemailer while using Tool Router? Yes, absolutely. You can configure which Enginemailer 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 Enginemailer data and credentials are handled as safely as possible. --- [See all toolkits](https://composio.dev/toolkits) · [Composio docs](https://docs.composio.dev/llms.txt)