About 13.9% of B2B addresses sit on catch-all domains, per MailerCheck's study of 33,000 lists. Those servers accept mail for any address, so a normal mailbox check can't tell a real person from a typo. Most verifiers return "unknown" and leave the guess to you.
I'm building skink, an email verification API that tries to answer those addresses instead of skipping them. Every result comes back with a confidence score, a plain-English reason, and one field, safe_to_send, to branch on.
Real-time email verification API — actual SMTP handshakes, not just syntax checks. Resolves catch-alls, even behind Proofpoint/Mimecast, where most tools return "unknown." Every result ships reasons[] and a calibrated confidence score, never laundered into a false "deliverable." MCP server for Claude/Cursor, or bulk CSV. Unknown results are free. We verify your list and stop there — encrypted at rest, retention you set. 100 free credits, no card.
