How to connect Mailboxlayer to Claude

Claude is Anthropic's AI assistant, available on the web, in the desktop app, and on mobile. Cowork is its agent for knowledge work, and it runs on all of those surfaces too. Connected to your apps, Claude can work with your files and services to accomplish complex tasks on your behalf.

This guide walks you through the easiest and most secure way to connect your Mailboxlayer account to Claude via Composio Connect, enabling it to check if this email address is real, validate a list of customer emails, verify if a domain accepts emails, and more such actions on your behalf without compromising your account security.

Setup is the same on Claude Web, Desktop, and Cowork, and you only need to do it once. The connector is tied to your account, so it's available in all three.

Connecting Mailboxlayer to Claude Web, Desktop, and Cowork

Two ways to add the Composio connector. Pick whichever you prefer.

1. Add with one click

Click the button. Claude opens with the Composio connector filled in. Click Add, then go to step 2.

Add to Claude

Add manually

In Claude Desktop, click Customize in the left sidebar, then select Connectors and click the + icon at the top.

Click Add custom connector and paste in the Composio MCP server URL:

The Mailboxlayer MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Mailboxlayer account. It provides structured and secure access to real-time email validation services, so your agent can check email syntax, verify domains, assess SMTP deliverability, and analyze email quality on your behalf.

• Instant email address validation: Prompt your agent to check if any email address is syntactically correct and conforms to standard formats.
• Domain verification and analysis: Automatically verify if the email's domain exists and is configured to accept messages, helping prevent bounced emails.
• SMTP deliverability check: Let your agent confirm whether messages can actually be delivered to a given address using live SMTP checks.
• Disposable and role-based address detection: Identify if an email is from a throwaway provider or a generic role account to enhance signup quality and reduce spam.
• Quality scoring and risk assessment: Retrieve flags and meta-scores that help your agent rate the reliability and trustworthiness of any email address instantly.