A customer asks an AI voice agent a question and waits. The agent already has an answer, it's midway through generating a long, multi-paragraph response, but the customer hears nothing for five seconds. By the time an answer arrives, the customer is frustrated, confused, and no longer paying attention

Text-to-speech integrations create exactly that gap. A one-sentence response might generate in 600 milliseconds, but the full response takes five seconds, and the integration waits for all of it before synthesis starts

This post shows how to close that gap. We stream each sentence to a hosted Kokoro-82M text-to-speech (TTS) model on Amazon SageMaker AI as soon as an agent produces it, so synthesis begins on sentence one instead of the finished response. Getting that audio back to a browser needs its own solution too, so we also cover both transports for doing it and what each costs in practice