Google has updated the Gemini Interactions API's Managed Agents to include environment hooks, explicit model selection, and free tier access. These capabilities build on previous releases introducing background tasks and remote MCP server integration.
- Gemini 3.6 Flash is now the default model for the antigravity-preview-05-2026 agent, with options to select Gemini 3.5 Flash or 3.5 Flash-Lite.
- Environment hooks allow custom scripts to run before or after tool calls using a .agents/hooks.json configuration file.
- Managed agents are now available on free tier projects without active billing.
- Budget controls via max_total_tokens cap consumption, pausing execution safely when limits are reached.
- Scheduled execution with triggers automates recurring tasks using persistent sandboxes.
These updates turn managed agents into cost-controlled, scheduled workers that operate autonomously inside real development environments.