LiveAvatar (formerly HeyGen Interactive / Streaming Avatar)

Overview

Best for: Teams that want HeyGen-quality stock avatars with a cheap avatar-only mode on top of an existing voice agent.

At a glance

Price is LITE mode (1 credit/min) at Business credit rate; FULL mode is 2 credits/min (about $0.16-$0.19). Free plan 10 credits/month. Old HeyGen Streaming API deprecated.

Features

• bring your own LLM
• bring your own TTS
• lip sync from any audio (LITE)
• push-to-talk mode
• session memory across sessions
• sandbox mode that does not consume credits
• iframe embed
• transcripts API

Pricing

Free tier: 10 credits per month (about 5 FULL minutes or 10 LITE minutes); sandbox mode is free for development.

Source: docs.liveavatar.com

Setup

1. Sign up at app.liveavatar.com and copy an API key from the Developers page.
2. Pick a public avatar or one migrated from HeyGen.
3. Backend: POST /v1/sessions/token with mode FULL or LITE (use is_sandbox: true while developing).
4. Backend: POST /v1/sessions/start with that token and pass the returned WebRTC credentials to the browser.
5. Frontend: join with the LiveAvatar Web SDK (or your LiveKit room in LITE mode); stop the session via API when done.

Endpoint

https://api.liveavatar.com/v1/sessions/token

Authentication

X-API-KEY header for minting session tokens; session token for start/stop

// Server-side: mint a session token, then start the session
const H = {
  "X-API-KEY": process.env.LIVEAVATAR_API_KEY,
  "Content-Type": "application/json",
};
const tokRes = await fetch("https://api.liveavatar.com/v1/sessions/token", {
  method: "POST",
  headers: H,
  body: JSON.stringify({
    mode: "FULL",              // or "LITE" for avatar-only
    avatar_id: process.env.AVATAR_ID,
    max_session_duration: 600, // seconds
    interactivity_type: "CONVERSATIONAL",
    is_sandbox: true,          // no credits while developing
  }),
});
const { data } = await tokRes.json();
// data.session_id, data.session_token
// Next: POST https://api.liveavatar.com/v1/sessions/start with the
// session token (see Start Session reference for the exact auth
// form), then hand the WebRTC credentials to the Web SDK.
// github.com/heygen-com/liveavatar-web-sdk

Written from the current docs. Check the vendor's SDK version before you ship.

Warnings

Plus 9 warnings that apply to all avatars and live video APIs. See category warnings.

Limits

• Sessions cannot start without credits for at least one minute
• Without overage enabled, sessions end automatically when credits run out
• max_session_duration must not exceed your tier's limit (limit values not published in docs checked)
• Rate limits: 10 req/s per API key; 5 req/s per session token on start/stop/keep-alive (HTTP 429)

Models and products

Docs and sources

Docs

• Overview
• Credits and subscriptions
• Create session token
• LITE mode lifecycle
• Changelog
• HeyGen streaming deprecation

Sources used

• docs.liveavatar.com/docs/faq/credits.md
• docs.liveavatar.com/api-reference/sessions/create-session-token.md
• docs.liveavatar.com/changelog.md
• docs.liveavatar.com/docs/interactive-avatar-migration-guide