How to integrate Instantly MCP with Mastra AI

This guide walks you through connecting Instantly to Mastra AI using the Composio tool router. By the end, you'll have a working Instantly agent that can create a new cold email campaign, add a new lead to your campaign, check unread emails in your inbox through natural language commands. This guide will help you understand how to give your Mastra AI agent real control over a Instantly account through Composio's Instantly MCP server. Before we dive in, let's take a quick look at the key ideas and tools involved.

Instantly logoInstantly
Api Key

Instantly is a platform for automating cold email outreach, managing leads, and optimizing deliverability. Get better results from email campaigns with minimal manual effort.

115 Tools

Introduction

This guide walks you through connecting Instantly to Mastra AI using the Composio tool router. By the end, you'll have a working Instantly agent that can create a new cold email campaign, add a new lead to your campaign, check unread emails in your inbox through natural language commands.

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

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

Also integrate Instantly with

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 Instantly tools
  • Connect Mastra's MCP client to the Composio generated MCP URL
  • Fetch Instantly 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 Instantly 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 Instantly MCP server, and what's possible with it?

The Instantly MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Instantly account. It provides structured and secure access to your campaigns, leads, and outreach tools, so your agent can perform actions like launching new campaigns, managing leads, tracking inbox statistics, and handling API credentials on your behalf.

  • Automated campaign creation and management: Ask your agent to launch new cold email campaigns or update existing ones, streamlining your outreach workflow without manual setup.
  • Lead and lead list management: Let your agent add new leads, organize them into lists, or enrich them with AI-driven insights to maximize your campaign effectiveness.
  • Email verification and deliverability tracking: Direct your agent to check the verification status of email addresses or run inbox placement tests to monitor and improve deliverability across providers.
  • Inbox activity monitoring: Fetch unread email counts or campaign engagement metrics, helping you stay on top of your outreach performance in real time.
  • API key and webhook automation: Have your agent create or delete API keys for secure integrations, or set up webhooks to receive instant notifications about important Instantly events.

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:
  • Node.js 18 or higher
  • A Composio account with an active API key
  • An OpenAI API key
  • Basic familiarity with TypeScript
2

Getting API Keys for OpenAI and Composio

OpenAI API Key
  • Go to the OpenAI dashboard 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.
  • Go to Settings and copy your API key.
  • This key lets your Mastra agent talk to Composio and reach Instantly through MCP.
3

Install dependencies

bash
npm install @composio/core @mastra/core @mastra/mcp @ai-sdk/openai dotenv

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
4

Set up environment variables

bash
COMPOSIO_API_KEY=your_composio_api_key_here
COMPOSIO_USER_ID=your_user_id_here
OPENAI_API_KEY=your_openai_api_key_here

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
5

Import libraries and validate environment

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,
});
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
6

Create a Tool Router session for Instantly

typescript
async function main() {
  const session = await composio.create(
    composioUserID as string,
    {
      toolkits: ["instantly"],
    },
  );

  const composioMCPUrl = session.mcp.url;
  console.log("Instantly MCP URL:", composioMCPUrl);
What's happening:
  • create spins up a short-lived MCP HTTP endpoint for this user
  • The toolkits array contains "instantly" for Instantly access
  • session.mcp.url is the MCP URL that Mastra's MCPClient will connect to
7

Configure Mastra MCP client and fetch tools

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);
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 Instantly toolkit
8

Create the Mastra agent

typescript
const agent = new Agent({
    name: "instantly-mastra-agent",
    instructions: "You are an AI agent with Instantly tools via Composio.",
    model: "openai/gpt-5",
  });
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
9

Set up interactive chat interface

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: {
        instantly: 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);
});
What's happening:
  • messages keeps the full conversation history in Mastra's expected format
  • agent.generate runs the agent with conversation history and Instantly 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

Complete Code

Here's the complete code to get you started with Instantly and Mastra AI:

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: ["instantly"],
  });

  const composioMCPUrl = session.mcp.url;

  const mcpClient = new MCPClient({
    id: composioUserID as string,
    servers: {
      instantly: {
        url: new URL(composioMCPUrl),
        requestInit: {
          headers: session.mcp.headers,
        },
      },
    },
    timeout: 30_000,
  });

  const composioTools = await mcpClient.getTools();

  const agent = new Agent({
    name: "instantly-mastra-agent",
    instructions: "You are an AI agent with Instantly 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: { instantly: 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 Instantly 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
TOOLS

Supported Tools

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

Check Custom Tracking Domain Status

Tool to check Custom Tracking Domain (CTD) status for email accounts.

Activate Campaign

Tool to activate or resume a paused campaign.

Add Leads in Bulk

Tool to add multiple leads in bulk to a campaign or list.

Get API Keys

Tool to retrieve paginated list of API keys for organization.

Bulk Assign Leads

Tool to bulk assign leads to organization users.

Get Campaigns Analytics Overview

Tool to get analytics overview for one or multiple campaigns.

Import Campaign from Export

Tool to import a campaign from exported data.

Check DFY Email Account Order Domains

Tool to check domain availability for DFY email account orders.

Check Email Verification Status

Tool to check status of an email verification job.

Count Launched Campaigns

Tool to retrieve the count of launched campaigns.

Count Leads from SuperSearch

Tool to count leads matching supersearch filter criteria.

Count Unread Emails

Tool to retrieve the count of unread emails.

Create AI Enrichment

Tool to create an AI enrichment job for a campaign or lead list.

Create API Key

Creates a new API key with specified permissions for the Instantly API.

Create Block List Entry

Tool to create a new block list entry for a specific email or domain.

Create Campaign

Tool to create a new campaign.

Create Custom Tag

Tool to create a new custom tag for organizing accounts and campaigns.

Create Inbox Placement Test

Tool to create an inbox placement test.

Create Lead

Tool to create a new lead.

Create Lead List

Tool to create a new lead list.

Create Subsequence

Creates an automated follow-up subsequence for a campaign.

Create SuperSearch Enrichment

Tool to create a supersearch enrichment job for a list or campaign.

Create Webhook

Tool to create a new webhook endpoint.

Delete API Key

Tool to delete an API key.

Delete Block List Entry

Tool to delete a blocked email or domain entry by its ID.

Delete Campaign

Tool to delete a campaign.

Delete Custom Tag

Tool to delete a custom tag by its ID.

Delete Lead

Tool to delete a lead by its ID.

Delete Lead Label

Tool to delete a lead label by ID.

Delete Lead List

Tool to delete a lead list by ID.

Delete Subsequence

Delete a subsequence from a campaign by its UUID.

Delete Webhook

Tool to delete a webhook.

Delete Whitelabel Domain

Tool to delete the whitelabel domain from current workspace.

List Pre-warmed Up DFY Domains

Tool to retrieve a list of pre-warmed up domains ready for DFY email account orders.

Disable Account Warmup

Tool to disable the warm-up process for email accounts.

Duplicate Campaign

Tool to duplicate an existing campaign.

Duplicate Subsequence

Tool to duplicate an existing subsequence to a specified parent campaign.

Enable Account Warmup

Tool to enable the warm-up process for email accounts.

Export Campaign

Tool to export campaign data to JSON format.

Get Account Campaign Mappings

Tool to retrieve campaigns associated with an email account.

Get Daily Account Analytics

Tool to retrieve daily account analytics showing emails sent per day for each account.

Get Accounts Warmup Analytics

Tool to retrieve warmup analytics for specified email accounts.

Get Audit Logs

Tool to retrieve audit log records for tracking system activities.

Get Block List Entry

Tool to retrieve a specific blocked email or domain entry by its ID.

Get Campaign

Tool to retrieve campaign details.

Get Campaign Analytics

Tool to retrieve analytics for campaigns.

Get Campaign Sending Status

Tool to retrieve campaign sending status diagnostics explaining why a campaign may not be sending emails or is sending slower than expected.

Get Campaign Steps Analytics

Tool to retrieve analytics data broken down by campaign steps and variants.

Get Current Workspace

Tool to retrieve current workspace details based on API key.

Get Custom Tag

Tool to retrieve a specific custom tag by ID.

Get Custom Tag Mappings

Tool to retrieve custom tag mappings that connect tags to resources like campaigns and email accounts.

Get Daily Campaign Analytics

Tool to retrieve daily analytics for a campaign.

Get DFY Email Account Order Accounts

Tool to retrieve DFY (Done-For-You) email account order accounts.

Get Email Service Provider Options

Tool to retrieve email service provider options for inbox placement tests.

Get Inbox Placement Analytics Stats By Date

Tool to retrieve time-series statistics for inbox placement test results by date.

Get Inbox Placement Test

Tool to retrieve inbox placement test results.

Get Lead

Tool to retrieve details of a specific lead by its ID.

Get Lead Label

Tool to retrieve a specific lead label by ID.

Get Lead List

Tool to retrieve details of a specific lead list by its ID.

Get CRM Phone Numbers

Tool to retrieve all phone numbers associated with your organization.

Get Similar DFY Email Account Order Domains

Tool to generate similar available domain suggestions for DFY email account orders.

Get Subsequence

Tool to retrieve a specific subsequence by its ID.

Get SuperSearch Enrichment

Tool to retrieve supersearch enrichment configuration and status for a list or campaign.

Get Lead List Verification Stats

Tool to retrieve verification statistics for a lead list.

Get Webhook

Tool to retrieve details of a specific webhook subscription.

Get Webhook Event

Tool to retrieve details of a specific webhook event.

Get Webhook Events Summary

Tool to retrieve webhook events summary with success and failure statistics.

Get Webhook Events Summary By Date

Tool to retrieve webhook event summaries grouped by date.

Get Webhook Event Types

Tool to retrieve all available webhook event types.

Get Workspace Billing Plan Details

Tool to retrieve workspace billing plan details.

Get Inbox Placement Deliverability Insights

Tool to retrieve deliverability insights for inbox placement tests.

Get Inbox Placement Analytics Stats By Test ID

Tool to retrieve aggregated inbox placement analytics statistics for specified test IDs.

Create Lead Label

Tool to create a custom lead label for categorizing leads.

List Email Accounts

Tool to list all email accounts for the authenticated user.

List Block List Entries

Tool to list blocked emails or domains from blocklist.

List Campaigns

Tool to list all campaigns.

List Custom Tags

Tool to list custom tags.

List DFY Email Account Orders

Tool to list DFY email account orders.

List Emails

Tool to list emails.

List Inbox Placement Blacklist & SpamAssassin Reports

Tool to list inbox placement blacklist & SpamAssassin reports.

List Inbox Placement Tests

Tool to list inbox placement tests.

List Lead Lists

Tool to list all lead lists.

List Leads

Tool to list leads.

List Webhook Events

Tool to list webhook events.

List Webhooks

Tool to list configured webhooks.

Mark Thread As Read

Tool to mark all emails in a specific thread as read.

Merge Leads

Tool to merge multiple leads into a single lead.

Move Leads

Tool to move leads from one campaign to another.

Update Lead Label

Tool to update an existing lead label by ID.

Patch SuperSearch Enrichment Settings

Tool to update auto-update and skip settings for SuperSearch enrichment.

Patch Webhook

Tool to update an existing webhook configuration.

Pause Campaign

Tool to pause an active campaign.

Pause Subsequence

Tool to pause an active campaign subsequence.

Remove Lead From Subsequence

Tool to remove a lead from a campaign subsequence.

Resume Subsequence

Tool to resume a paused campaign subsequence.

Search Campaigns by Lead Email

Tool to search campaigns by a lead's email address.

Set Whitelabel Domain

Tool to set whitelabel agency domain for current workspace.

Share Campaign

Tool to share a campaign.

Run SuperSearch Enrichment

Tool to run all enrichments for resource leads or unenriched leads.

Test Accounts Vitals

Tool to test IMAP/SMTP connectivity and account vitals for email accounts.

Test Webhook

Tool to send a test payload to verify a webhook is working.

Toggle Resource

Tool to assign or unassign custom tags to resources like accounts and campaigns.

Update Block List Entry

Tool to update a blocked email or domain entry.

Update Campaign

Tool to update details of a campaign.

Update Custom Tag

Tool to update an existing custom tag's label or description.

Update Inbox Placement Test

Tool to update an inbox placement test.

Update Lead

Tool to update a lead's details.

Update Lead Interest Status

Tool to update a lead's interest status.

Update Lead List

Tool to update details of a specific lead list by its ID.

Update Subsequence

Tool to update a campaign subsequence entity.

Update Current Workspace

Tool to update the current workspace details.

Verify Email

Tool to initiate email verification.

Get Admin Workspace Group Member

Tool to retrieve admin workspace details for the current sub workspace.

Get Workspace Member by ID

Tool to retrieve details of a specific workspace member by ID.

Add Workspace Member

Tool to add a new member to workspace with email and role.

FAQ

Frequently asked questions

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

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 Instantly tools.

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

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