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.