Flash 3.5 Medium
Think of Medium as a highly optimized, lightning-fast "copilot on steroids." It relies heavily on Gemini 3.5 Flash's raw 12x inference speed tricks for quick iterations. Because it manages context conservatively, it's designed for execution, immediate file edits, and inline debugging where you don't want the agent losing itself in massive codebase context loops.
Flash 3.5 High
High is the fully autonomous "agentic" mode. When toggled to High, Antigravity hands the steering wheel entirely to the model. The primary agent will automatically spin off specialized subagents, run asynchronous terminal processes, and continuously modify code across multiple folders.
Warning: Because High utilizes full recursive loop capabilities (reverting, committing, testing, and modifying on its own), it is notoriously token-hungry and can easily consume a Pro quota in a single heavy session if a problem causes a regression loop.