A static base decays while it sits: 23% of contacts switch jobs within a year (ZoomInfo 2025) and 40% of addresses go dead within two years (NeverBounce). A CSV is a snapshot; a check at the moment of use is a state. TAPAC runs the SMTP check inside your agent's loop, so the address is verified right before the send instead of weeks before — 2–5% bounce against 10–35% for static bases (TAPAC's published agent guide). Pay per use: $0.10–0.50 per contact, 100 searches free, no annual contract, no seat license. Wire it as an MCP server with `npx -y @tapacapi/mcp` and get a key at https://tapacapi.com/get-key. How many addresses in your last send were verified within the hour you mailed them?