Gemini CLI Dies Today: Your Complete Migration Guide to Antigravity CLI

Gemini CLI stops serving most consumer users today, June 18, 2026. If you use Gemini CLI through the free tier, Google AI Pro, or Google AI Ultra, your migration window is no longer "soon." It is today.

Google's official transition post says the replacement is Antigravity CLI, exposed as the agy command and tied to the broader Antigravity 2.0 agent surface (Google Developer Blog). The practical takeaway: move your working config now, verify your plugins and MCP servers, and do not assume your old Gemini CLI setup will keep working after the cutoff.

There is one important exception. Google says organizations on Gemini Code Assist Standard or Enterprise licenses, and users with paid Gemini Enterprise Agent Platform API keys, are not affected by this consumer shutdown. If that is you, you have more room to plan. If you are a free, AI Pro, or AI Ultra user, treat this as a last-day migration.

Why Google Is Forcing the Move

This is not just a rename. Gemini CLI was a TypeScript/Node.js open-source project under Apache 2.0, and Google previously emphasized that developers could inspect how it worked (Google Blog). Antigravity CLI is a separate Go-built product connected to Google's newer multi-agent harness.

Google's argument is consolidation: one agent platform across terminal and desktop workflows, not a standalone CLI drifting away from Antigravity. At I/O 2026, Google framed Antigravity 2.0 and Antigravity CLI as two surfaces for the same productivity system (I/O developer keynote recap).

The upside is real: Antigravity is designed around async, background, multi-agent work. The downside is also real: you are moving from a community-inspectable Apache 2.0 tool into a closed product. Hacker News users called out that trust shift directly, noting that the Antigravity CLI repo did not expose the same source-code surface as Gemini CLI (HN discussion).

Quick Decision Table

Migration Checklist

1. Back up your Gemini CLI setup

First, capture your working state:

``bash cp -R ~/.gemini ~/.gemini.backup-2026-06-17 ``

Then list dependencies:

``bash gemini /extensions find . -name GEMINI.md -maxdepth 4 ``

If your team stores MCP settings outside ~/.gemini, back those files up too. The migration risk is usually local workflow glue, not the base install.

2. Install Antigravity CLI

Use the official Antigravity download/install flow from Google's docs, not a copied third-party script. The official migration path is documented at antigravity.google/docs/gcli-migration.

After install, confirm the binary:

``bash agy --version agy ``

On first launch, Antigravity should detect legacy Gemini CLI configuration and start its migration flow. Note every extension, setting, and workspace prompt it claims to import.

3. Authenticate

For personal use:

``bash agy auth login ``

For a Google Cloud project-backed flow:

``bash agy auth login --project YOUR_GCP_PROJECT_ID ``

Then close and reopen the terminal and run a trivial prompt:

``bash agy "summarize this repository in five bullets" ``

If you get a sign-in prompt again, fix auth before moving on. Flaky auth makes every plugin or MCP failure harder to diagnose.

4. Convert Extensions to Plugins

Gemini CLI Extensions become Antigravity Plugins. Google's migration docs describe compatibility and conversion, while early community reports still recommend checking each plugin manually (official docs, GitHub discussion).

Run:

``bash agy plugin import gemini agy plugin list ``

Then test each plugin with the smallest command that proves it works. Do not count "listed" as "migrated."

5. Fix MCP Configs: serverUrl Is the Key

This is the migration footgun.

In Gemini CLI configs, MCP servers may use:

``json { "url": "https://example.com/mcp" } ``

or:

``json { "httpUrl": "https://example.com/mcp" } ``

For Antigravity CLI, rename those keys to:

``json { "serverUrl": "https://example.com/mcp" } ``

The synthesis flags this as a silent failure risk: old keys may not error; the MCP server may simply not connect. Verify each server with a real tool call.

6. Verify the Migration Before You Trust It

Run this list now, before end of day:

• agy auth login persists across terminal restarts
• agy plugin list shows expected converted plugins
• Every plugin completes one real task
• Every MCP server connects and completes one real tool call
• Workspace GEMINI.md instructions still load where you expect them
• Your team can reproduce the install from documented steps, not your shell history
• You have a rollback copy of ~/.gemini

If you use Antigravity's async multi-agent features, test them in a low-risk repository first. Google highlights terminal sandboxing, credential masking, and hardened Git policies (Google Developer Blog); still, prove those controls before using the tool on sensitive repos.

The Trust Tradeoff

The community reaction is split for good reasons. Some power users like the new async subagent workflow and Docker-backed sandbox reports in early migration threads (GitHub discussion). Others object to losing the Apache 2.0 inspectability that made Gemini CLI feel safer and more community-owned.

There is also recent security context. The Hacker News reported in April 2026 that Google patched an Antigravity IDE vulnerability involving prompt injection and file-search behavior (The Hacker News). That does not mean Antigravity CLI is unsafe. It does mean security-sensitive teams should treat the migration as a toolchain change.

Bottom Line

If you are on free, AI Pro, or AI Ultra Gemini CLI, migrate today. Install agy, import plugins, rename MCP url and httpUrl keys to serverUrl, and run real verification checks before June 18.

Antigravity CLI may become the stronger long-term surface because it is built around multi-agent workflows. But the last-mile migration risk is local: broken plugins, silent MCP failures, stale auth, and a changed trust model. Handle those today, and today's Gemini CLI shutdown becomes a planned cutover instead of a surprise outage.