MailboxValidator MCP server

This is a small helper that lets your AI check email addresses for you. You ask about an address, and it tells you whether that address looks real and reachable, or risky. It is handy if you send marketing emails or newsletters and want fewer bounces.

What this MCP server does

You type a question about an email address in your AI chat, like whether it is valid. Your AI passes that address to this helper program. The helper sends it to the MailboxValidator service, which runs a series of checks on it. The service sends the result back, and your AI explains it to you in plain words in the chat.

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What you can do with it

• Check whether an email address is valid and reachable
• Spot disposable or temporary email addresses
• Tell whether an address comes from a free email provider
• Catch addresses that are likely to bounce
• Screen a list of addresses before you send a campaign
• Check the reputation of an email address

Try asking your AI

• “Is john@example.com a valid email address?”
• “Is this email a fake or disposable one: test@mailinator.com”
• “Is sarah@gmail.com a free email address?”
• “Will this address bounce if I send to it: info@somecompany.com”

What it gives back to you

You get a short answer in the chat, like whether the address is valid, disposable, or from a free provider. Behind that answer is a set of check results, such as syntax, domain and mail server checks, and a reputation score. Your AI reads those results and sums them up for you. If something goes wrong, you get an error message instead.

Before you start

Who it's for

Marketing and email people who send campaigns and want to avoid bounces, plus anyone who wants a quick sanity check on an email address.