Skip to main content
You’ll mint an ephemeral OpenAI client secret on your backend, create an Avaturn session bound to it, and connect from the browser. The conversation engine is OpenAI Realtime.

​
Prerequisites

  • Avaturn API key (dashboard)
  • OpenAI API key with Realtime API access
  • Backend in Node.js or Python; any JS framework on the frontend

​
1. Mint an OpenAI client secret

On your backend, exchange your OpenAI API key for a short-lived client secret. 
from openai import AsyncOpenAI

openai = AsyncOpenAI(api_key="<OPENAI_API_KEY>")
secret = await openai.realtime.client_secrets.create(
    expires_after={"seconds": 600, "anchor": "created_at"},
    session={
        "type": "realtime",
        "model": "gpt-realtime",
        "instructions": "You are a friendly assistant. Keep replies brief.",
        "audio": {"output": {"voice": "marin"}},
    },
)
client_secret = secret.value  # ek_...

​
2. Create an Avaturn session

import httpx

async with httpx.AsyncClient() as http:
    r = await http.post(
        "https://api.avaturn.live/api/v1/sessions",
        headers={"Authorization": "Bearer <AVATURN_API_KEY>"},
        json={
            "conversation_engine": {
                "type": "openai-realtime",
                "client_secret": client_secret,
            }
        },
    )
    r.raise_for_status()
    session = r.json()  # { "session_id": "...", "token": "..." }
Never expose <AVATURN_API_KEY> or <OPENAI_API_KEY> to the browser. Only the per-session token belongs there.

​
3. Connect from the frontend

npm install @avaturn-live/web-sdk

import { AvaturnHead } from "@avaturn-live/web-sdk";

const root = document.querySelector<HTMLDivElement>("#avaturn-video")!;
const avatar = new AvaturnHead(root, {
  sessionToken: session.token,
  audioSource: true,
});

await avatar.init();
The avatar joins the room, requests microphone access, and starts conversing. Speak into the mic — the avatar responds.

​
4. Clean up

await avatar.dispose();
dispose() tears down the local SDK state. The backend session expires shortly after the user disconnects (default 60s). To terminate immediately, call DELETE /api/v1/sessions/{id} from your backend.

​
Next steps

OpenAI Realtime engine

Tools, custom prompts, turn detection, transcripts.

Cartesia engine

Drive the avatar from a Cartesia Line agent.

SDK methods

Devices, mute, attach to a new DOM node.

SDK events

Speech start/end, lifecycle, transcripts.