Agentic voice: VoiceStudio as a TTS/STT provider

August 6, 2026 · View on GitHub

VoiceStudio exposes an OpenAI-compatible API, so any agent framework that speaks to OpenAI's audio endpoints can use your local VoiceStudio for speech — in your own cloned voice, with nothing leaving your machine. You bring the agent runtime; VoiceStudio is the voice.

This is "agentic v1": VoiceStudio is a provider, not the orchestrator. You wire your own agent (a support line, a desk assistant, a Discord persona) and point its TTS/STT at VoiceStudio.

Scope. This page covers VoiceStudio-as-provider. Outbound phone calls are a separate, deferred milestone (they need a paid carrier — there is no fully-local path to the PSTN) and ship only behind explicit consent guardrails. See the roadmap in docs/competitive-analysis.md (§R1).

The endpoints

VoiceStudio serves these on http://localhost:3900/v1 (or your remote backend URL):

OpenAI routeVoiceStudio support
POST /v1/audio/speechTTS. model = engine id, voice = a voice-profile id (your clone) or preset, response_format incl. pcm and wav, speed. Default output is 24 kHz.
POST /v1/audio/transcriptionsSTT (Whisper-family).
GET /v1/audio/voiceslist available voices (VoiceStudio extension).

A contract test (tests/test_agentic_provider_contract.py) pins this request shape in CI, so the recipes below won't silently break.

pipecat (BSD-2) runs as a Python library inside your own process — no extra server. Point its OpenAI TTS/STT services at VoiceStudio:

from pipecat.services.openai.tts import OpenAITTSService
from pipecat.services.openai.stt import OpenAISTTService

tts = OpenAITTSService(
    base_url="http://localhost:3900/v1",
    api_key="not-needed-locally",        # any string; VoiceStudio ignores it unless OMNIVOICE_API_KEY is set
    voice="<your-voice-profile-id>",     # from GET /v1/audio/voices, or "default"
    model="omnivoice",                   # or any installed engine id
    sample_rate=24000,                   # matches VoiceStudio's default output
)

stt = OpenAISTTService(
    base_url="http://localhost:3900/v1",
    api_key="not-needed-locally",
)

Drop those into any pipecat pipeline (VAD, turn-taking, and LLM stay local too). A minimal runnable example is in examples/agentic/pipecat_minimal.py.

LiveKit Agents

LiveKit Agents (Apache-2.0) needs a LiveKit media server alongside, but its OpenAI plugin takes the same base_url:

from livekit.plugins import openai

tts = openai.TTS(base_url="http://localhost:3900/v1", api_key="x", voice="<profile-id>")
stt = openai.STT(base_url="http://localhost:3900/v1", api_key="x")

Choose LiveKit over pipecat only when you need its WebRTC/SIP scale; for a single local agent, pipecat is lighter.

Remote backend

Running VoiceStudio on a remote GPU box? Use that backend's URL as base_url and pass its OMNIVOICE_API_KEY as the api_key — the same bearer the rest of the app uses. Keep it on your tailnet, not the open internet.

Use your own voice responsibly

When an agent speaks in a cloned voice, prefer a profile you've marked verified own voice (Settings → a voice profile → Voice ownership). That consent lock is what gates the heavier agentic features as they land, and it's the honest default for "an AI is speaking as me."