Route calls, manage models, handle interruptions, and scale to thousands of concurrent conversations. The AI call routing layer so you build what makes your voice AI unique
You built the voice agent in a week. Six months later, you're still wiring telephony, fixing turn-taking, and debugging why calls drop at scale.
SIP trunking, WebRTC, carrier connections — you're spending months on telecom plumbing before shipping a single call.
Your voice activity detection cuts people off mid-sentence or waits awkwardly for five seconds. Neither is acceptable.
Your agent talks over the caller or freezes when interrupted. Every demo hides this problem.
The caller goes off-script and your state machine doesn't know what to do. The conversation collapses.
It works at 50 concurrent calls. At 5,000, everything falls apart — dropped audio, timeouts, queues backing up.
Dropped audio, model timeouts, partial transcription — calls are failing and nobody's getting alerted.
14 capabilities, one SDK. Every feature built for multimodal voice AI models from day one.
Connect to any carrier. production-ready without building a telecom stack.
Handle thousands of simultaneous calls. Scale up and down automatically based on demand.
AI outbound calling with scheduling, pacing, retry logic, and real-time progress dashboards.
Real-time token and cost tracking per call, per agent, per model. Know spend before the invoice.
Voice activity detection tuned for real conversations. Distinguishes pauses from finished thoughts.
Your agent yields when interrupted and resumes gracefully, like a human colleague.
Define flows, handle branching, manage context across turns without custom orchestration code.
Stream audio directly to GPT-4o Realtime, Gemini Live, or any multimodal voice AI model.
Switch agents mid-call. Deploy patches without dropping conversations. Zero-downtime updates.
Automatic "mm-hmm" and "got it" signals that make conversations feel natural and present.
Detect caller silence. Re-engage or gracefully close — stop burning minutes on dead air.
Recognize voicemail before your agent starts a conversation with a recording.
Dropped audio, timeouts, tool failures — calls adapt instead of crashing.
Button presses, account numbers, legacy phone trees — full compatibility with existing systems.
Other tools handle calls. VOX handles calls AND connects to the systems that make them reliable. For teams evaluating a Vapi alternative or LiveKit alternative, VOX is the orchestration layer that ships with the full stack.
| Feature | VOX | LiveKit Agents | Vapi | Pipecat |
|---|---|---|---|---|
| Call orchestration | Full-stack, production-ready | Yes (developer framework) | Yes (managed) | Yes (open-source) |
| Built-in observability | LENS - full stack, unified | Session-level (30-day retention) | Basic logs + dashboards | Requires third-party (OTel) |
| Integrated testing | DOJO - real audio evals | Third-party required | Simulated only (AI-to-AI) | Third-party required |
| Governance layer | SENSEI - system-level guardrails | Build your own | Compliance certs only | Build your own |
| Audio-native models | Native speech-to-speech | Supported (not default) | Cascaded-first | Supported (not default) |
| Agent hot-swap | Zero-downtime, mid-call | Manual | Squad handoffs only | Manual |
Focus on what makes your voice AI different. See VOX in a live demo.