Migrating from Gemini CLI to Antigravity CLI: A Guide

On May 19, 2026, Google announced that it would shut down the old Gemini CLI for all Free, Pro, and Ultra plans on June 18. Two weeks after this guide is published, the gemini command will stop processing requests. Migrating from Gemini CLI to Antigravity CLI with the agy command is the only way to stay with Google tools. agy is built in Go and starts tens of times faster.

If you have anything running on Gemini CLI—CI scripts, nightly cron jobs, the Gemini Code Assist IDE extension—this guide explains how to migrate in one evening without breaking anything.

Which Gemini CLI users are affected by the June 18, 2026 change?#

This is not a “complete shutdown of the project,” but a cutoff for the three most popular plans. Who is affected:

From the official Google Developers Blog:

If you used the Free plan, like most individual developers, and are thinking “but I have a paid account”—check exactly how your API key is billed. AI Pro is not Cloud billing; it is a personal Google AI subscription, and it will be disabled. Cloud billing with a paid project will not be disabled.

Why is Google shutting down Gemini CLI at all?#

The old gemini started in “hundreds of milliseconds” because Node.js needed to warm up. The new agy is built as a single static Go binary and starts in “milliseconds.” For CI and scripts that call the CLI hundreds of times per run, the difference is significant.

What Google says about the speed and the reason:

All the key Gemini CLI features have moved over:

• Agent Skills — the .gemini/skills/ folder now lives in .agents/skills/.
• Hooks — the same events (PreToolUse, PostToolUse, etc.); the syntax has barely changed.
• Subagents — work as before, and their configuration is migrated automatically.
• Extensions — renamed Antigravity plugins and imported with one command.

What did NOT migrate seamlessly: MCP servers and old scripts that directly access .gemini/config.json. MCP configurations may break and need to be rewritten manually. There is a separate section on this below.

Google is not closing the Gemini CLI open-source project:

That means you can fork it and continue using it with your own Gemini API key. But this is now a paid setup through Cloud billing; the free Code Assist arrangement is over.

How to install Antigravity CLI: commands for macOS, Linux, and Windows#

Before you start, do a quick self-check: which plan are you on? If you have a paid Cloud project with no June 18 deadline, migration is useful but not urgent. If you are on Free/Pro/Ultra and have something running on the CLI, switch now, while the plans are still active, so you can compare behavior on the same task.

macOS and Linux

One-liner using curl:

curl -fsSL https://antigravity.google/cli/install.sh | bash

The script detects the platform, downloads the agy binary, checks its checksum, and puts it in ~/.local/bin. If this folder is not in PATH, add it:

echo 'export PATH="$HOME/.local/bin:$PATH"' >> ~/.zshrc
source ~/.zshrc

Check that the binary is visible:

which agy
agy --version

Windows (PowerShell)

irm https://antigravity.google/cli/install.ps1 | iex

The binary will be installed in C:\Users\[your_name]\AppData\Local\agy\bin. The installer will update PATH automatically, but open a new PowerShell window to reload the variables.

Windows (CMD)

If PowerShell is blocked by your corporate policy:

curl -fsSL https://antigravity.google/cli/install.cmd -o install.cmd && install.cmd && del install.cmd

Verify the installation

After installation on any OS, run:

agy doctor

The command checks the binary version, whether a config exists, authentication, and network access to antigravity.google. If it cannot reach Google, the issue is with your region or proxy.

Authentication

The first time you run agy without arguments, it launches a setup wizard:

1. Choose an interface theme.
2. Choose an authentication method: Google OAuth (for personal accounts) or an API key.
3. Optionally, import the config from .gemini/ right away.

If you choose OAuth, a browser will open and redirect you to accounts.google.com; you need to consent to data sharing. After that, the CLI works.

How to migrate config and plugins from .gemini to .agents#

Step by step:

1. agy plugin import gemini

   Run the command from any folder. It will migrate global plugins from ~/.gemini/ to ~/.agents/. For workspace plugins (next to the project), run the command inside the project folder.

2. mv .gemini/skills/ .agents/skills/

   Move skills by manually renaming the folder. The file format inside is the same; there is no need to rewrite the markdown.

3. agy inspect

   Shows which plugins, skills, hooks, and subagents are active. Compare this with the list you had in Gemini CLI—there should be no omissions.

4. agy config --edit

   Opens the config in the default editor ($EDITOR). If something was not picked up automatically, edit it manually.

5. agy doctor

   Final check: binary, authentication, plugins, network. If all four are green, config migration is complete.

I would leave the old .gemini/ folder in place as a backup for a month, in case something was missed. After you have used Antigravity for a week and confirmed that everything is there, you can delete it.

If you work with AGENTS.md as a universal config for all AI tools, you do not need to touch it. Antigravity CLI reads AGENTS.md from the same folder as Claude Code or Codex.

Which environment variables need to be changed?#

Complete replacement table:

If you have GitHub Actions that pass through secrets, open Settings -> Secrets -> Actions and rename the keys. The values themselves stay the same (the Google API key did not change during migration).

Check all places that might contain GEMINI_:

# Find mentions throughout the project
grep -rn "GEMINI_" . --include="*.yml" --include="*.yaml" --include="*.sh" --include=".env*" 2>/dev/null

# In dotfiles
grep -nE "GEMINI_" ~/.zshrc ~/.bashrc ~/.bash_profile ~/.config/fish/config.fish 2>/dev/null

After replacing them, restart the terminal and check presence without printing the secret. Do not enable shell tracing or copy key values into logs. Presence alone does not prove authorization; inspect agy doctor separately:

if [ -n "${AV_API_KEY:-}" ]; then
    printf 'AV_API_KEY is set\n'
else
    printf 'AV_API_KEY is missing or empty\n'
fi
agy doctor        # should show “authorized”

What most often breaks during the transition and how to fix it#

Checklist of initial problems:

1. MCP servers. If you used mcp_servers in .gemini/config.json, they might not be picked up after agy plugin import gemini. Check with agy inspect—there will be an mcp section. If it is empty or has errors, rewrite it manually with agy config --edit. The format is described in the official Antigravity documentation (look for the MCP section).

2. Custom hooks. If you had a bash script in .gemini/hooks/ that read $GEMINI_API_KEY, it will break. Find such places: bash

   grep -rn "GEMINI_" .agents/hooks/ 2>/dev/null
   

   Replace the variables.

3. CI/CD. In GitHub Actions or GitLab CI, change steps that use the gemini command to agy. The binary name in the installer may differ, so create an abstraction using the $CLI_CMD variable.

4. IDE Extension. The Gemini Code Assist extension for VS Code will be disabled along with the CLI. The replacement is Antigravity IDE (a separate VS Code fork) or AGENTS.md in any other AI editor.

5. @[file] loading. In early Antigravity CLI builds, the @src/file.ts command for loading a file into context had bugs. Update to the latest version: agy update.

If something critical breaks and cannot be fixed within an hour, a temporary solution for the Free plan is to stay on Gemini CLI until June 18 while setting up the migration on a separate repository branch. Time limit: 14 days.

Is it worth staying with Google tools after June 18?#

Antigravity 2.0 can be considered as a backup option for cases where your primary tool (Claude Code or Codex) is not suitable. For a detailed look at what it is good and bad at, see the guide to Google Antigravity 2.0.

A short breakdown of what to do depending on your situation:

Migration checklist in 15 minutes#

1. Install Antigravity CLI

   curl -fsSL https://antigravity.google/cli/install.sh | bash (macOS/Linux) or irm https://antigravity.google/cli/install.ps1 | iex (Windows PowerShell).

2. Start agy and authenticate

   Without arguments: agy. Choose OAuth or an API key.

3. Import plugins from .gemini

   agy plugin import gemini—this migrates extensions globally. Run it again inside the project folder for workspace plugins.

4. Move skills

   mv .gemini/skills/ .agents/skills/. The file contents stay as they are.

5. Replace environment variables

   In ~/.zshrc/~/.bashrc and .env files: GEMINI_API_KEY → AV_API_KEY, GEMINI_PROJECT_ID → AV_PROJECT_ID, GEMINI_REGION → AV_REGION. Restart the terminal.

6. Verify the installation

   agy doctor—all four items (binary, authentication, plugins, network) should be green.

7. Run a test task

   agy "write a README for the project in the current folder"—check that the result is similar to what Gemini CLI produced.

8. Update GitHub Actions / GitLab CI

   Change the command name and secrets from GEMINI_* to AV_*.

9. Keep .gemini/ as a backup

   You can delete it 1–2 weeks after confirming that everything works.

And lastly: June 18 does not mean “all your projects will go down.” It means the free channel is being disabled. Paid Cloud API access remains, the Gemini CLI repository remains, and forks are possible. If you used the Free plan, you need to decide before June 18; otherwise, the next gemini "something" will return an authorization error.