Gemini 3.8 Live Extended Thinking audio-to-audio

Gemini 3.8 Live Extended Thinking is our high-reasoning audio-to-audio model recommended when higher background reasoning is required for complex, multi-step problem solving during real-time voice interactions. It processes background reasoning and asynchronous tool calls while streaming continuous audio responses.

Documentation #

Visit the Live API guide for full coverage of features and capabilities.

gemini-3.8-live-extended-thinking #

| Property | Description |

|---|---|
| Model code | `gemini-3.8-live-extended-thinking` | 

| Supported data types | Inputs Text, images, audio, video Output Text and audio | | Token limits ^[*] | Input token limit 131,072 Output token limit 65,536 | | Capabilities | Supported Not supported Not supported Not supported Supported (Async only) Not supported Not supported Supported Supported Not supported Supported Not supported | | Consumption options | Not supported | | Versions | model version patterns for more details. | | Latest update | September 2026 |

| Model card | Model card |

Upgrading to Gemini 3.8 Live Extended Thinking #

Gemini 3.8 Live Extended Thinking introduces background reasoning during live audio sessions. When integrating this model, update your client state management to handle asynchronous reasoning signals:

• Asynchronous reasoning protocol : When interacting with models that use asynchronous reasoning,turnComplete: true no longer indicates that the model is idle. The server may continue processing background reasoning or tool calls. Your client must continue listening for subsequent server messages (such as tool calls or audio frames) afterturnComplete: true arrives.
• Monitoring interaction_status : Use the interaction_status field on incoming server messages to determine current server state:
  • IN_PROGRESS : The server is actively processing user input, running background reasoning, or awaiting responses for asynchronous tool calls. Additional model output or tool calls may follow.
  • IDLE : The server has finished all processing, reasoning, and tool calls. The session is idle and waiting for user input.
• Asynchronous function calling : Only asynchronous non-blocking execution (behavior: NON_BLOCKING ) is supported. Synchronous blocking mode is not supported and returns a hard error. Function scheduling configurations are not supported.
• Thinking configuration : Configure background reasoning usingthinking_config in your setup configuration (thinking_level :low ,medium , orhigh ). Note thatMINIMAL is not supported.
• Client content updates :send_client_content is supported throughout the entire session lifecycle with explicit roles (user ormodel ). Settingturn_complete=true immediately interrupts active generation.
• Proactive audio : Permanently enabled. Settingproactive_audio: false returns an error.

For a feature comparison across all Live API models, see the
[Model comparison](https://ai.google.dev/gemini-api/docs/live-api/capabilities#model-comparison)

table.