AI voice agents: what they are and how they work in 2026

AI voice agents combine speech-to-text, language models, and text-to-speech to automate natural, multi-turn conversations for customer support, scheduling, and qualification. Case studies cite agents handling up to 77% of L1-L2 support and 30-45% productivity gains, with full-stack costs of $0.01-$0.05 per minute or AssemblyAI’s Voice Agent API at $4.50/hour.