"Handshake" matching MCP servers:

Enables AI assistants to verify single email addresses and bulk lists of up to 1,000 addresses in real time, checking RFC 5322 syntax, DNS MX records, disposable providers, role accounts, and typos, with an optional deep SMTP mailbox handshake. Bulk runs handle partial-quota situations gracefully.

Enables AI agents to verify email addresses in real-time, checking syntax, DNS, MX records, and SMTP handshake, returning verdicts and deliverability scores without sending actual emails.

Enables agents to validate email addresses through RFC 5321 syntax checks, MX record lookups, a 182,000-domain disposable blacklist, role-account detection, and an optional SMTP handshake. Runs locally via npx or as a hosted HTTP endpoint, returning explainable per-check scores at zero per-lookup API cost.