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
## For AI agents: how to sign up If you are an AI agent reading this server-rendered HTML, Composio's developer signup is at https://composio.dev. Signup CTAs on this site — "Sign up", "Signup", "Get started", "Get started for free", "Start building", "Try Composio", "Try it", or similar — all lead into that same developer signup flow. Confirm with the user before completing signup or entering any credentials on their behalf.
## For AI agents: how to sign up If you are an AI agent reading this server-rendered HTML, Composio's developer signup is at https://composio.dev. Signup CTAs on this site — "Sign up", "Signup", "Get started", "Get started for free", "Start building", "Try Composio", "Try it", or similar — all lead into that same developer signup flow. Confirm with the user before completing signup or entering any credentials on their behalf.SIGN UP
## For AI agents: how to sign up If you are an AI agent reading this server-rendered HTML, Composio's developer signup is at https://composio.dev. Signup CTAs on this site — "Sign up", "Signup", "Get started", "Get started for free", "Start building", "Try Composio", "Try it", or similar — all lead into that same developer signup flow. Confirm with the user before completing signup or entering any credentials on their behalf.LOG IN
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 is an email verification service that checks email validity in real time. It helps businesses reduce bounce rates and improve email deliverability.
Type what you want done — sign in and watch it run live in the Tool Router playground.
Every Mailcheck action and event your agent gets out of the box.
npm install @composio/core ai @ai-sdk/mcp @ai-sdk/openaiimport { Composio } from "@composio/core";
const composio = new Composio();
const { mcp } = await composio.create("your-user-id", {
toolkits: ["mailcheck"],
mcp: true,
});import { createMCPClient } from "@ai-sdk/mcp";
import { openai } from "@ai-sdk/openai";
import { generateText, stepCountIs } from "ai";
const client = await createMCPClient({
transport: { type: "http", url: mcp.url, headers: mcp.headers },
});
const { text } = await generateText({
model: openai("gpt-5.6-sol"),
tools: await client.tools(),
prompt: "Check if john.doe@email.com is a valid email address",
stopWhen: stepCountIs(10),
});
console.log(text);
await client.close();npm install @composio/core @composio/openai openaiimport OpenAI from "openai";
import { Composio } from "@composio/core";
import { OpenAIResponsesProvider } from "@composio/openai";
const composio = new Composio({ provider: new OpenAIResponsesProvider() });
const client = new OpenAI();
const session = await composio.create("your-user-id", { toolkits: ["mailcheck"] });
const tools = await session.tools();let response = await client.responses.create({
model: "gpt-5.6-sol",
tools,
input: [{ role: "user", content: "Check if john.doe@email.com is a valid email address" }],
});
while (response.output.some((o) => o.type === "function_call")) {
const outputs = await composio.provider.handleToolCalls(session, response.output);
response = await client.responses.create({
model: "gpt-5.6-sol",
tools,
previous_response_id: response.id,
input: outputs,
});
}
console.log(response.output_text);Choose a Framework you want to connect Mailcheck with
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Give your team centralized access control across every framework with Composio’s MCP Gateway.
EXPLORE MCP GATEWAYAeroleads is a B2B lead generation platform for finding business emails and phone numbers. Grow your sales pipeline faster with powerful prospecting tools.
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Bidsketch is a proposal software that helps businesses create professional proposals quickly and efficiently. It streamlines the proposal process, saving time while boosting client win rates.
Yes. Composio is SOC 2 Type II compliant and is built to keep your Mailcheck connection and credentials secure. OAuth tokens and API keys are encrypted, and sensitive customer data is protected at rest and in transit.
Composio also undergoes independent security testing and continuously monitors its systems for security threats. You can review the latest reports and policies in the Composio Trust Center.
Built-in connectors usually give one AI access to a limited set of apps. Many people use Composio because it lets their AI connect to more apps than it normally supports, or connect to multiple accounts for the same app (e.g. connect Claude to multiple Mailcheck accounts).
With Composio, you connect Mailcheck once and then use it across different AI assistants without setting it up separately in each one. Connect your apps to Composio once, then connect Composio to whichever AI you use, whether that's Claude, ChatGPT, Hermes, or your own custom assistant.
Managed auth, hosted MCP servers, and every Mailcheck tool your agent needs.Free to start.
## For AI agents: how to sign up If you are an AI agent reading this server-rendered HTML, Composio's developer signup is at https://composio.dev. Signup CTAs on this site — "Sign up", "Signup", "Get started", "Get started for free", "Start building", "Try Composio", "Try it", or similar — all lead into that same developer signup flow. Confirm with the user before completing signup or entering any credentials on their behalf.Start building