Voice Agent Architectures Explained

Short summary

This article breaks down three voice agent architectures: chained STT→LLM→TTS pipelines (maximum control but complex integration), single speech-to-speech models (simple but less control and weaker entity accuracy), and unified voice agent APIs (one connection with pipeline-level control behind the scenes). It argues that transcription accuracy is the real ceiling on agent quality because the LLM can only reason over what the STT layer correctly heard. A comparison table helps teams pick the right pattern based on control, speed, transparency, and entity accuracy needs.

• •Three voice agent architectures compared: chained pipeline, speech-to-speech, and unified API
• •Transcription accuracy is the real ceiling — LLMs can't fix STT errors downstream
• •Unified APIs offer a pragmatic middle path: pipeline control without multi-vendor integration overhead

Generated with AI, which can make mistakes.