--- name: gemini-live-api-dev description: Use this skill when building real-time, bidirectional streaming applications with the Gemini Live API, or migrating legacy Live models (2.0/2.5/3.1) to Gemini 3.8 Live. Covers WebSocket-based audio/video/text streaming, voice activity detection (VAD), background reasoning (extended thinking), asynchronous function calling, session management, ephemeral tokens, live transcription, and live translation. SDKs covered - google-genai (Python), @google/genai (JavaScript/TypeScript). --- # Gemini Live API Development Skill ## Overview The Live API enables **low-latency, real-time voice and video interactions** with Gemini over WebSockets. It processes continuous streams of audio, video, or text to deliver immediate, human-like spoken responses and background reasoning. Key capabilities: - **Bidirectional audio streaming** — real-time mic-to-speaker conversations - **Background reasoning (extended thinking)** — multi-step background reasoning with spoken conversational fillers - **Live streaming transcription** — real-time speech-to-text with interim and finalized streams - **Video streaming** — send camera/screen frames alongside audio - **Text input/output** — send and receive text within a live session - **Audio transcriptions** — get text transcripts of both input and output audio - **Voice Activity Detection (VAD)** — automatic server VAD, client-side Hybrid VAD, and manual Push-to-Talk - **Asynchronous function calling** — non-blocking tool execution while audio continues streaming - **Full-session client content** — inject and update conversation turns mid-stream - **Session management** — context compression, session resumption, GoAway signals - **Ephemeral tokens** — secure client-side authentication > [!NOTE] > The Live API connects directly via **WebSockets**. For WebRTC support or simplified integration, use a [partner integration](#partner-integrations). ## Models ### Current Models (Use These) - `gemini-3.8-live` — Default option for most low-latency voice agent experiences and real-time dialogue without reasoning delays. Supports interleaved reasoning, asynchronous function calling by default (`behavior: NON_BLOCKING`), and full-session client content updates. - `gemini-3.8-live-extended-thinking` — High-reasoning audio-to-audio model recommended when higher background reasoning is required during live interactions. Processes background reasoning and async tool calls (`behavior: NON_BLOCKING` required) while streaming continuous spoken conversational fillers; lifecycle managed via `interaction_status` (`IN_PROGRESS` vs `IDLE`). - `gemini-3.5-transcribe-live` — Real-time streaming speech-to-text with interim hypotheses, finalized transcripts, smart formatting, and Hybrid VAD. - `gemini-3.5-live-translate-preview` — Real-time speech-to-speech streaming translation across 70+ languages. > [!WARNING] > **Legacy Models (`gemini-3.1-flash-live-preview`, `gemini-2.5-flash-native-audio-*`, `gemini-live-2.5-flash-preview`, `gemini-2.0-flash-live-001`)**: Read [`references/migration.md`](references/migration.md) for breaking protocol changes (`behavior: "NON_BLOCKING"`, `thinking_level`, `interaction_status`, `send_client_content`). ## SDKs - **Python**: `google-genai` >= `2.3.0` — `pip install -U google-genai` - **JavaScript/TypeScript**: `@google/genai` >= `2.3.0` — `npm install @google/genai` > [!WARNING] > Legacy SDKs `google-generativeai` (Python) and `@google/generative-ai` (JS) are **deprecated**. Never use them. ## Partner Integrations To streamline real-time audio/video app development, use a third-party integration supporting the Gemini Live API over **WebRTC** or **WebSockets**: - [LiveKit](https://docs.livekit.io/agents/models/realtime/plugins/gemini/) — Use the Gemini Live API with LiveKit Agents. - [Pipecat by Daily](https://docs.pipecat.ai/guides/features/gemini-live) — Create a real-time AI chatbot using Gemini Live and Pipecat. - [Fishjam by Software Mansion](https://docs.fishjam.io/tutorials/gemini-live-integration) — Create live video and audio streaming applications with Fishjam. - [Vision Agents by Stream](https://visionagents.ai/integrations/gemini) — Build real-time voice and video AI applications with Vision Agents. - [Voximplant](https://voximplant.com/products/gemini-client) — Connect inbound and outbound calls to Live API with Voximplant. - [Firebase AI SDK](https://firebase.google.com/docs/ai-logic/live-api?api=dev) — Get started with the Gemini Live API using Firebase AI Logic. ## Audio Formats - **Input**: Raw PCM, little-endian, 16-bit, mono. 16kHz native (will resample others). MIME type: `audio/pcm;rate=16000` - **Output**: Raw PCM, little-endian, 16-bit, mono. 24kHz sample rate. > [!IMPORTANT] > Use `send_realtime_input` / `sendRealtimeInput` for all real-time streaming user input (audio, video, **and text**). On Gemini 3.8 models, `send_client_content` / `sendClientContent` is supported across the full session lifecycle with explicit roles (`user` or `model`) to inject conversation context (`turn_complete=true` unconditionally interrupts active generation). > [!WARNING] > Do **not** use `media` in `sendRealtimeInput`. Use the specific keys: `audio` for audio data, `video` for images/video frames, and `text` for text input. --- ## Quick Start ### Authentication #### Python ```python from google import genai client = genai.Client(api_key="YOUR_API_KEY") ``` #### JavaScript ```js import { GoogleGenAI } from '@google/genai'; const ai = new GoogleGenAI({ apiKey: 'YOUR_API_KEY' }); ``` ### Connecting to the Live API #### Python ```python from google.genai import types config = types.LiveConnectConfig( response_modalities=[types.Modality.AUDIO], system_instruction=types.Content( parts=[types.Part(text="You are a helpful assistant.")] ) ) async with client.aio.live.connect(model="gemini-3.8-live", config=config) as session: pass # Session is active ``` #### JavaScript ```js const session = await ai.live.connect({ model: 'gemini-3.8-live', config: { responseModalities: ['audio'], systemInstruction: { parts: [{ text: 'You are a helpful assistant.' }] } }, callbacks: { onopen: () => console.log('Connected'), onmessage: (response) => console.log('Message:', response), onerror: (error) => console.error('Error:', error), onclose: () => console.log('Closed') } }); ``` ### Sending Text #### Python ```python await session.send_realtime_input(text="Hello, how are you?") ``` #### JavaScript ```js session.sendRealtimeInput({ text: 'Hello, how are you?' }); ``` ### Sending Audio #### Python ```python await session.send_realtime_input( audio=types.Blob(data=chunk, mime_type="audio/pcm;rate=16000") ) ``` #### JavaScript ```js session.sendRealtimeInput({ audio: { data: chunk.toString('base64'), mimeType: 'audio/pcm;rate=16000' } }); ``` ### Sending Video #### Python ```python # frame: raw JPEG-encoded bytes await session.send_realtime_input( video=types.Blob(data=frame, mime_type="image/jpeg") ) ``` #### JavaScript ```js session.sendRealtimeInput({ video: { data: frame.toString('base64'), mimeType: 'image/jpeg' } }); ``` ### Receiving Audio and Text > [!IMPORTANT] > A single server event can contain **multiple content parts simultaneously** (e.g., audio chunks and transcript). Always process **all** parts in each event to avoid missing content. #### Python ```python async for response in session.receive(): content = response.server_content if content: # Audio — process ALL parts in each event if content.model_turn: for part in content.model_turn.parts: if part.inline_data: audio_data = part.inline_data.data # Transcription if content.input_transcription: print(f"User: {content.input_transcription.text}") if content.output_transcription: print(f"Gemini: {content.output_transcription.text}") # Interruption if content.interrupted is True: pass # Stop playback, clear audio queue ``` #### JavaScript ```js // Inside the onmessage callback const content = response.serverContent; if (content?.modelTurn?.parts) { for (const part of content.modelTurn.parts) { if (part.inlineData) { const audioData = part.inlineData.data; // Base64 encoded } } } if (content?.inputTranscription) console.log('User:', content.inputTranscription.text); if (content?.outputTranscription) console.log('Gemini:', content.outputTranscription.text); if (content?.interrupted) { /* Stop playback, clear audio queue */ } ``` --- ## Background Reasoning (Extended Thinking) Use `gemini-3.8-live-extended-thinking` when your voice agent must evaluate complex data, plan multiple steps, or handle long-running tools. The model speaks natural conversational fillers (e.g. *"Checking flight options now..."*) while executing asynchronous tools in the background. Key requirements: - **Thinking config**: Set `thinking_config=types.ThinkingConfig(thinking_level="low")` (`"minimal"` | `"low"` | `"medium"` | `"high"`). - **Non-blocking tools**: All function declarations **must** set `behavior="NON_BLOCKING"`. Synchronous blocking mode is not supported and returns an error. - **Lifecycle tracking (`interaction_status`)**: Do **not** rely on `turn_complete=True` alone to detect turn completion. Monitor `message.interaction_status` (Python) / `message.interactionStatus` (JS): - `"IN_PROGRESS"`: Server is reasoning, speaking conversational fillers, or waiting for async tool responses. - `"IDLE"`: Server has completed all background reasoning and tool calls; session is ready for user input. See [`references/migration.md`](references/migration.md) and the [Thinking in Live API Guide](https://ai.google.dev/gemini-api/docs/live-api/thinking.md.txt) for complete Python and JavaScript implementation examples. --- ## Live Translation (Gemini Live Translate) The Live API supports real-time, low-latency streaming translation of speech (audio) across 70+ languages. For full details on options and capabilities, see the [Live Translate Guide](https://ai.google.dev/gemini-api/docs/live-api/live-translate.md.txt). ### Model - `gemini-3.5-live-translate-preview` — The recommended translation model for all Live Translate use cases. ### Configuration (`TranslationConfig`) To enable translation, specify a `TranslationConfig` object inside your live session setup: - **Python SDK**: Configure the connection using `translation_config` on `LiveConnectConfig`: ```python config = types.LiveConnectConfig( response_modalities=[types.Modality.AUDIO], translation_config=types.TranslationConfig( target_language_code="es", # Target language code (e.g. es, fr, pl) echo_target_language=True, ), input_audio_transcription=types.AudioTranscriptionConfig(), output_audio_transcription=types.AudioTranscriptionConfig(), ) ``` - **Raw WebSockets**: Place `translationConfig` inside `generationConfig`: ```json { "setup": { "model": "models/gemini-3.5-live-translate-preview", "generationConfig": { "responseModalities": ["AUDIO"], "translationConfig": { "targetLanguageCode": "es", "echoTargetLanguage": true } } } } ``` --- ## Live Streaming Transcription (Gemini Live Transcribe) The Live API supports real-time streaming speech-to-text over WebSockets with low-latency interim hypotheses, finalized transcripts, and Hybrid VAD. For full details, see the [Live Transcription Guide](https://ai.google.dev/gemini-api/docs/live-api/live-transcribe.md.txt) and [Colab Cookbook](https://colab.research.google.com/github/google-gemini/cookbook/blob/main/quickstarts/Get_started_transcribe.ipynb). ### Model - `gemini-3.5-transcribe-live` ### Modes - `smart`: cleans up filler words, resolves inline self-corrections, and structures formatting. - `verbatim` (default): exact word-for-word transcript. ### Python ```python config = types.LiveConnectConfig( response_modalities=["TEXT"], input_audio_transcription=types.AudioTranscriptionConfig(), ) async with client.aio.live.connect(model="gemini-3.5-transcribe-live", config=config) as session: # Stream audio await session.send_realtime_input(audio=types.Blob(data=chunk, mime_type="audio/pcm;rate=16000")) # Hybrid VAD: notify turn end on client-detected silence for zero latency await session.send_realtime_input(audio_stream_end=True) ``` ### JavaScript ```javascript const session = await ai.live.connect({ model: 'gemini-3.5-transcribe-live', config: { responseModalities: ['text'], inputAudioTranscription: { mode: 'smart' } }, callbacks: { onmessage: (msg) => { if (msg.serverContent?.interimInputTranscription) { console.log('Interim:', msg.serverContent.interimInputTranscription.text); } if (msg.serverContent?.inputTranscription) { console.log('Final:', msg.serverContent.inputTranscription.text); } } } }); session.sendRealtimeInput({ audio: { data: chunkBase64, mimeType: 'audio/pcm;rate=16000' } }); session.sendRealtimeInput({ audioStreamEnd: true }); // Hybrid VAD ``` ### Raw WebSockets ```json { "setup": { "model": "models/gemini-3.5-transcribe-live", "generationConfig": { "responseModalities": ["TEXT"], "speechConfig": { "voiceConfig": {} } }, "inputAudioTranscription": { "mode": "smart" } } } ``` --- ## Limitations - **Response modality** — Only `TEXT` **or** `AUDIO` per session, not both. Native audio models output audio (`response_modalities=["AUDIO"]`); enable `output_audio_transcription` if you need text transcripts. - **Audio-only session** — 15 min without compression - **Audio+video session** — 2 min without compression - **Connection lifetime** — ~10 min (use session resumption) - **Context window** — 128k input tokens / 64k output tokens - **Code execution / URL context** — Not supported ## Upgrading & Migration For step-by-step migration checklists and protocol deltas when upgrading from `gemini-3.1-flash-live-preview`, `gemini-2.5-flash-native-audio-*`, or `gemini-2.0-flash-live-001` to **Gemini 3.8 Live** or **Gemini 3.8 Live Extended Thinking**, read [`references/migration.md`](references/migration.md). ## Best Practices 1. **Use headphones** when testing mic audio to prevent echo/self-interruption 2. **Enable context window compression** for sessions longer than 15 minutes 3. **Implement session resumption** to handle connection resets gracefully 4. **Use ephemeral tokens** for client-side deployments — never expose API keys in browsers 5. **Use `send_realtime_input`** for real-time user input (audio, video, text). Use `send_client_content` with explicit `user`/`model` roles to inject context turns mid-stream 6. **Send `audioStreamEnd` / `audio_stream_end`** (Hybrid VAD) when the mic is paused or user finishes speaking 7. **Clear audio playback queues** on interruption signals (`interrupted: true`) 8. **Process all parts** in each server event — events can contain multiple content parts 9. **Monitor `interaction_status`** (`IN_PROGRESS` vs `IDLE`) when using `gemini-3.8-live-extended-thinking` rather than relying on `turn_complete` alone ## Documentation Lookup ### When MCP is Installed (Preferred) If the **`search_docs`** tool (from the Google MCP server) is available, use it as your **only** documentation source: 1. Call `search_docs` with your query 2. Read the returned documentation 3. **Trust MCP results** as source of truth for API details — they are always up-to-date. > [!IMPORTANT] > When MCP tools are present, **never** fetch URLs manually. MCP provides up-to-date, indexed documentation that is more accurate and token-efficient than URL fetching. ### When MCP is NOT Installed (Fallback Only) If no MCP documentation tools are available, fetch from the official docs index: **llms.txt URL**: `https://ai.google.dev/gemini-api/docs/llms.txt` This index contains links to all documentation pages in `.md.txt` format. Use web fetch tools to: 1. Fetch `llms.txt` to discover available documentation pages 2. Fetch specific pages (e.g., `https://ai.google.dev/gemini-api/docs/live-session.md.txt`) ### Key Documentation Pages > [!IMPORTANT] > Those are not all the documentation pages. Use the `llms.txt` index to discover available documentation pages - [Live API Overview](https://ai.google.dev/gemini-api/docs/live.md.txt) — getting started, raw WebSocket usage - [Thinking in Live API](https://ai.google.dev/gemini-api/docs/live-api/thinking.md.txt) — background reasoning, conversational fillers, interaction_status, non-blocking tools - [Model Card: Gemini 3.8 Live](https://ai.google.dev/gemini-api/docs/models/gemini-3.8-live) — default low-latency voice agent model & migration guide - [Model Card: Gemini 3.8 Live Extended Thinking](https://ai.google.dev/gemini-api/docs/models/gemini-3.8-live-extended-thinking) — high-reasoning voice model & upgrading guide - [Live Transcription](https://ai.google.dev/gemini-api/docs/live-api/live-transcribe.md.txt) — real-time speech-to-text, interim hypotheses, smart formatting, and Hybrid VAD - [Live Translate](https://ai.google.dev/gemini-api/docs/live-api/live-translate.md.txt) — configuration options and capabilities for translation - [Live API Capabilities Guide](https://ai.google.dev/gemini-api/docs/live-guide.md.txt) — voice config, transcription config, VAD configuration, media resolution - [Live API Tool Use](https://ai.google.dev/gemini-api/docs/live-tools.md.txt) — function calling (sync and async), Google Search grounding - [Session Management](https://ai.google.dev/gemini-api/docs/live-session.md.txt) — context window compression, session resumption, GoAway signals - [Ephemeral Tokens](https://ai.google.dev/gemini-api/docs/ephemeral-tokens.md.txt) — secure client-side authentication for browser/mobile - [WebSockets API Reference](https://ai.google.dev/api/live.md.txt) — raw WebSocket protocol details - [Migration & Upgrading Guide](references/migration.md) — step-by-step checklists and code examples for Gemini 3.8 Live and Extended Thinking ## Supported Languages The Live API supports 70 languages including: English, Spanish, French, German, Italian, Portuguese, Chinese, Japanese, Korean, Hindi, Arabic, Russian, and many more. Native audio models automatically detect and switch languages.