> ## Documentation Index
> Fetch the complete documentation index at: https://docs.unify.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Voice

> Talk to your locally-running teammate in the browser

Real voice calls run the production fast-brain — interruption-handling,
telephony-aware — locally with sub-second latency. From the local chat
REPL, type `meet` to open a LiveKit browser session and speak through your
mic. Utterances follow the same Unify Meet path as production voice.

## What you need

Voice uses **LiveKit Cloud** for browser Meet sessions, plus one
speech-to-text and one text-to-speech provider (both have free tiers; pick
**one** TTS provider). The install wizard prompts for these; to add them
later, edit `~/.unity/unity/.env` and run `unify setup`.

| Variable                                               | Purpose                   | Where to get it                                                                                       |
| ------------------------------------------------------ | ------------------------- | ----------------------------------------------------------------------------------------------------- |
| `LIVEKIT_URL`, `LIVEKIT_API_KEY`, `LIVEKIT_API_SECRET` | Browser voice media       | [cloud.livekit.io](https://cloud.livekit.io)                                                          |
| `DEEPGRAM_API_KEY`                                     | Speech-to-text            | [console.deepgram.com](https://console.deepgram.com) — free tier                                      |
| `CARTESIA_API_KEY` *or* `ELEVEN_API_KEY`               | Text-to-speech (pick one) | [play.cartesia.ai](https://play.cartesia.ai) or [elevenlabs.io](https://elevenlabs.io) — free credits |

## How local voice works

Live calls run two coordinated brains:

* **Slow brain** (`ConversationManager`) — sees everything, decides
  deliberately, runs in the main process.
* **Fast brain** — a real-time LiveKit voice agent in a subprocess,
  sub-second latency, handles turn-taking autonomously.

They communicate over IPC. The slow brain steers the fast brain with
**SPEAK** (say exactly this), **NOTIFY** (here's context, decide what to
do), or **BLOCK** (do nothing; carry on). This is the same dual-brain
architecture the hosted product runs — locally you're just running both
halves on your own machine.

Phone calls over real telephony, video calls, and screen-share are part of
the hosted product at [console.unify.ai](https://console.unify.ai).