Google Announces Updates for Gemini API Managed Agents

Google has announced comprehensive updates for managed agents within the Gemini API. In line with these developments, Gemini 3.6 Flash has been assigned as the default model, while innovations such as environment hooks, budget audits, and free tier access have been introduced.

Core Capabilities of Managed Agents

Managed agents within the Gemini Interactions API coordinate processes such as reasoning, code execution, package installation, file management, and retrieving information from the web within an isolated cloud sandbox using a single API call.

Gemini 3.6 Flash as the Default Model

Gemini 3.6 Flash has been made the default model for the antigravity-preview-05-2026 agent. While this model offers balanced performance across reasoning, coding, and tool use, developers can also choose alternatives such as Gemini 3.5 Flash or Gemini 3.5 Flash-Lite if they prefer.

Security and Environment Hooks

Thanks to new environment hooks, custom scripts can be run before or after every tool call within the sandbox by adding an .agents/hooks.json configuration file. This allows tool calls to be blocked, audited, or inspected using command-line scripts or HTTP-type handlers.

Budget Controls and Free Tier

Managed agents are now also available in free tier projects. Additionally, new budget controls like max_total_tokens prevent tasks from getting out of hand by limiting total consumption, while scheduled triggers allow recurring tasks to be automated using cron schedules.