Email Validator MCP

Validate email addresses without sending mail. Checks the format, looks up the MX record, and flags disposable domains. No key required.

This file is self contained. It reads public data only and never writes to the machine. All output is bounded and honest about what could not be fetched.

Tools

• validate_email Check one email address: format, live MX records, disposable-domain status, role account (info@, support@) and whether it is a free provider.
• validate_batch Validate up to 25 addresses at once and get a count of well-formed, malformed and risky ones.
• check_domain Domain-level mail check: MX records, A records, and whether the domain is a disposable or free provider.
• normalize_email Canonical form of an address: lowercase the domain, drop the +tag, and remove Gmail dots, so duplicates collapse to one record.
• extract_emails Pull every unique email address out of a block of text, flagging any disposable domains.
• disposable_domains List the known disposable email domains this server checks against.
• email_auth_records The full anti-spoofing picture for a domain: MX hosts, SPF with its all-rule, DMARC policy and DKIM selectors.
• mx_health Every MX host for a domain, whether it resolves to an A record, and its reverse DNS.
• correct_typo Suggests the mail provider a mistyped domain probably meant, e.g. gmial.com -> gmail.com, without contacting the domain.

Usage

npm install
npm run build
node dist/index.js

MX records are resolved through the DNS of the sending machine. A missing MX record does not guarantee an inbox does not exist, the result is honest about that.

Premium tools

These tools need a license key:

• smtp_mailbox_check
• spf_evaluate

Buy a key at https://mcp-marketplace.io/server/io-github-mrfentmen-email-validator-mcp and set it in your MCP client config:

"env": { "MCP_LICENSE_KEY": "mcp_live_..." }

The key is checked against MCP Marketplace, cached for 24 hours, and keeps working offline once one check has succeeded. Every other tool on this server stays free.