Gemini CLI Is Moving to Antigravity CLI. What Developers Should Check Before June 18
A practical Antigravity CLI migration guide for Gemini CLI users covering the June 18 2026 timeline, agent workflows, hooks, skills, quotas, and safe rollout steps.
In This Article
What Changed at Google I/O 2026
Google announced Antigravity 2.0, Antigravity CLI, and an expanded agent ecosystem at Google I/O 2026. The important practical detail for developers is that Gemini CLI users are being encouraged to move to Antigravity CLI, and Google says Gemini CLI and Gemini Code Assist IDE extensions for individual free, AI Pro, and AI Ultra usage stop serving requests on June 18, 2026.
That makes "Antigravity CLI migration" a near-term developer task, not just a product announcement. If you use Gemini CLI in personal projects, coding experiments, classroom work, scripts, or team demos, inventory those workflows now so you do not discover the change during a release or deadline.
What Antigravity CLI Is For
Antigravity CLI is the terminal surface for Google's agent-first development platform. Google describes Antigravity 2.0 as a desktop home for orchestrating agents and Antigravity CLI as the lightweight terminal option for creating agents without a graphical interface.
The keywords to watch are agent workflows, Agent Skills, Hooks, Subagents, Extensions moving toward Antigravity plugins, and tighter connections with Google AI Studio, Android, Firebase, and the Gemini API. In plain terms: the command line is becoming less of a chat prompt and more of an agent runner.
Make a Migration Inventory First
Before installing anything, list where Gemini CLI appears today. Check shell aliases, npm scripts, README commands, internal docs, classroom notes, dotfiles, CI experiments, and copied prompt templates. Separate casual one-off usage from workflows that other people depend on.
For each workflow, write down the model, command, input files, output files, approval pattern, and any environment variables. This gives you a rollback plan and makes it easier to compare Gemini CLI behavior with Antigravity CLI behavior without relying on memory.
Test Agent Permissions Like Production Code
Agentic coding tools can read files, edit files, run commands, open browsers, call APIs, or use plugins depending on how they are configured. Treat the migration as a permissions review.
Start in a throwaway repository. Use a small task that has tests. Watch what files are read, what commands are proposed, and what artifacts are produced. If a workflow touches credentials, customer data, payment logic, deployment scripts, or infrastructure files, require human review before it becomes a default agent task.
Watch Quotas, Pricing, and Account Routing
Google's I/O posts also describe AI subscription changes and Antigravity usage limits. That matters because a CLI migration can change which account, plan, quota, or credit bucket a developer workflow uses.
Teams should document which Google account is approved for work usage, whether personal accounts are allowed, how usage is tracked, and what happens when quotas are hit. For solo developers, the practical step is simpler: check the account shown by the CLI before running long agent sessions.
A Safe Migration Checklist
Install Antigravity CLI in a non-critical environment. Recreate one Gemini CLI workflow at a time. Confirm file edits with diffs. Run tests after each agent change. Move reusable instructions into versioned project files instead of private memory. Keep Gemini CLI notes until June 18, 2026, but do not build new dependencies on a path that is being retired for your account type.
The right outcome is not just "the command runs." The right outcome is a repeatable agent workflow with clear permissions, visible artifacts, a known account, and a tested rollback path.