System class · No. 06
Voice Agents
AI agents that hold real-time voice conversations for calls, support, and assistants.
Voice agents hold real-time spoken conversations — answering and placing phone calls, running support lines, and powering assistants — by stitching speech-to-text, an LLM, and text-to-speech together under tight latency budgets. The differentiators are conversational latency and naturalness, telephony and SIP integration, and how gracefully the agent handles the hard parts of real calls: interruptions, silence, background noise, and a clean hand-off to a human when it's out of depth. Sub-second response time is what separates a natural conversation from an awkward one, so scrutinize end-to-end latency, not just the quality of the underlying model. Evaluate the available voices, how well the system handles barge-in when a caller talks over it, and how it manages turn-taking and context across a long call.
Integration surface matters too: check telephony providers, warm transfer to human agents, function calling into your back-end systems, and analytics on call outcomes. Most platforms price per minute of conversation, bundling speech, model, and telephony costs, sometimes with a monthly platform fee on top — so model your real call volume before comparing headline rates. Test with your own scripts, accents, and edge cases rather than the vendor's demo, because voice quality degrades fastest exactly where real callers live: noisy lines, fast talkers, and unexpected questions.
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Open-source index
Frequently asked
- What is a voice AI agent?
- A voice agent conducts natural, real-time voice conversations — answering and making calls, handling support, or acting as an assistant — by combining speech recognition, an LLM, and voice synthesis.
- How do I choose a voice agent platform?
- Prioritize conversational latency and naturalness, telephony/SIP integration, interruption handling, and how easily it hands off to a human. Test with your real call scripts.
- How much do voice agents cost?
- Typically per-minute usage pricing that bundles speech, model, and telephony costs; some platforms add a monthly fee.