Verifly checks email addresses before you send to them. Upload a CSV or call the REST API and every row comes back as ok, invalid, catch-all, disposable or unknown, after syntax, domain/MX and mailbox checks. There is no monthly subscription: packs start at 5,000 checks for $10, credits never expire, and new accounts get 100 free credits. It is built for cold-email teams, outbound agencies and developers: guides for Clay, n8n, Make, Zapier, HubSpot, Apollo, Smartlead and lemlist, plus a hosted MCP server at https://verifly.email/mcp so AI agents can verify an address before they email it.