Mailcheck MCP for AI Agents

Securely connect your AI agents and chatbots (Claude, ChatGPT, Cursor, etc) with Mailcheck MCP or direct API to verify email addresses, check deliverability, validate lists, and reduce bounces through natural language.

Mailcheck logoMailcheck
Api Key

Mailcheck is an email verification service that checks email validity in real time. It helps businesses reduce bounce rates and improve email deliverability.

2 Tools

Try Mailcheck now

Type what you want done — sign in and watch it run live in the Tool Router playground.

TOOL ROUTER PLAYGROUND
Mailcheck
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TOOLS

Supported Tools

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

Validate Domain

Tool to validate a domain for disposability, MX records, domain age, and spam indicators.

Verify Email Address

Tool to verify provided email address.

SETUP GUIDE

Connect Mailcheck MCP Tool with your Agent

1

Install Composio

typescript
npm install @composio/core ai @ai-sdk/openai @ai-sdk/mcp
Install the Composio SDK and Claude Agent SDK
2

Create Tool Router Session

typescript
import { Composio } from '@composio/core';

const composio = new Composio({ apiKey: 'your-api-key' });

console.log("Creating Tool Router session...");
const { mcp } = await composio.create('your-user-id');
console.log(`Tool Router session created: ${mcp.url}`);
Initialize the Composio client and create a Tool Router session
3

Connect to AI Agent

typescript
import { openai } from '@ai-sdk/openai';
import { experimental_createMCPClient as createMCPClient } from '@ai-sdk/mcp';
import { generateText, stepCountIs } from 'ai';

const client = await createMCPClient({
  transport: {
    type: 'http',
    url: mcp.url,
    headers: { 'x-api-key': 'your-composio-api-key' }
  }
});

const tools = await client.tools();

const { text } = await generateText({
  model: openai('gpt-4o'),
  tools,
  messages: [{ role: 'user', content: 'Verify if john.doe@email.com is a valid email address' }],
  stopWhen: stepCountIs( 5 )
});

console.log(`Agent: ${text}`);
Use the MCP server with your AI agent
SETUP GUIDE

Connect Mailcheck API Tool with your Agent

1

Install Composio

typescript
npm install @composio/openai
Install the Composio SDK
2

Initialize Composio and Create Tool Router Session

typescript
import OpenAI from 'openai';
import { Composio } from '@composio/core';
import { OpenAIResponsesProvider } from '@composio/openai';

const composio = new Composio({
  provider: new OpenAIResponsesProvider(),
});
const openai = new OpenAI({});
const session = await composio.create('your-user-id');
Import and initialize Composio client, then create a Tool Router session
3

Execute Mailcheck Tools via Tool Router with Your Agent

typescript
const tools = session.tools;
const response = await openai.responses.create({
  model: 'gpt-4.1',
  tools: tools,
  input: [{
    role: 'user',
    content: 'Check if john.doe@email.com is a valid email address'
  }],
});
const result = await composio.provider.handleToolCalls(
  'your-user-id',
  response.output
);
console.log(result);
Get tools from Tool Router session and execute Mailcheck actions with your Agent

Why Use Composio?

AI Native Mailcheck Integration

  • Supports both Mailcheck MCP and direct API based integrations
  • Structured, LLM-friendly schemas for reliable tool execution
  • Rich coverage for reading, writing, and querying your Mailcheck data

Managed Auth

  • Built-in OAuth handling with automatic token refresh and rotation
  • Central place to manage, scope, and revoke Mailcheck access
  • Per user and per environment credentials instead of hard-coded keys

Agent Optimized Design

  • Tools are tuned using real error and success rates to improve reliability over time
  • Comprehensive execution logs so you always know what ran, when, and on whose behalf

Enterprise Grade Security

  • Fine-grained RBAC so you control which agents and users can access Mailcheck
  • Scoped, least privilege access to Mailcheck resources
  • Full audit trail of agent actions to support review and compliance
FAQ

Frequently asked questions

Yes, Mailcheck requires you to configure your own API key credentials. Once set up, Composio handles secure credential storage and API request handling for you.

Yes! Composio's Tool Router enables agents to use multiple toolkits. Learn more.

Composio is SOC 2 and ISO 27001 compliant with all data encrypted in transit and at rest. Learn more.

Composio maintains and updates all toolkit integrations automatically, so your agents always work with the latest API versions.

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Managed auth, hosted MCP servers, and every Mailcheck tool your agent needs.Free to start.

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