How to build an AI voice assistant: Brand-aligned voice AI

This guide explains how to build an AI voice assistant by connecting speech to text, an LLM, and text to speech into one real-time pipeline, then adding a knowledge base, business tools, system instructions, and fallback rules. It covers architecture choices between raw APIs and the managed ElevenAgents platform, latency targets below 500 ms with voice activity detection, caller verification, human handoff, brand voice customization, and pre-launch testing for latency, interruptions, accuracy, and safety. Post-launch metrics such as containment, escalation rate, word error rate, hallucination rate, and CSAT are recommended for continued improvement.