How to Build an AI SDR Agent with Clay and GPT-5 Human SDRs cost $98K–$173K/year fully loaded; a Clay AI SDR agent with GPT-5 costs under $24K. Build yours step by step, from ICP list to booked calendar. May 8, 2026 • Luka Mrkić AI sales development representative Claygent GPT-5 cold email AI outbound sales sales automation