February 25, 2026

You can now dynamically replace the entire Think provider configuration during a live Voice Agent conversation using the new UpdateThink client message. This allows you to switch to a different LLM provider, change the model, set a completely new prompt, and reconfigure functions — all in a single message.

Unlike UpdatePrompt, which adds to the existing prompt, UpdateThink replaces the full Think provider configuration, giving you complete control over the agent's reasoning setup mid-conversation.

Example:

{
    "type": "UpdateThink",
    "think": {
        "provider": {
            "type": "open_ai",
            "model": "gpt-4o-mini"
        },
        "prompt": "You are a helpful voice assistant."
    }
}

The server confirms the change with a ThinkUpdated response message.

For more details, visit the UpdateThink documentation.