Static bases bounce at 10–35%; verification at the moment of use pulls that to 2–5%. The difference doesn't show up as a line item on your invoice — mail providers read bounces as a sender signal, reputation degrades quietly, and your next three campaigns pay the bill. The decay is baked in: 40% of addresses go dead within two years (NeverBounce) and 23% of contacts change jobs in a year (ZoomInfo 2025). The fix isn't a bigger list, it's checking each address inside the agent's runtime, seconds before send. TAPAC is a B2B contact engine with SMTP verification, delivered as an MCP server: npx -y @tapacapi/mcp, key at https://tapacapi.com/get-key — pay per use at $0.10–0.50 per contact, 100 free searches, no annual contract. How many bounces would your domain have to take before you actually noticed?