How to Fix the Antigravity 2.0 / IDE Launch Loop & Keep Your Agent Sidebar without Downgrading (Dual-Wield Guide) (tested on Windows 11 Pro) (JUST UPDATED with post-guide fix for "Agent Execution Terminated Due To Error")

EDIT: Reported Working on ARM64!

credit to u/R90nine for the report!

If today's Google I/O update completely broke your workspace, forced you into the new 2.0 "Agent Manager" prompt app, or locked you out of the classic code editor, the installer dependencies are conflicted. TAKE A DEEP BREATH. HALF THE INFORMATION OUT THERE IS FALSE. Many people have been getting the wrong idea because of this horribly botched update process. Google did NOT get rid of the ability to use IDE with the agent. The ONLY major change to the IDE itself in 2.0+ was moving the Agent Manager to a separate standalone app (Antigravity 2.0 Standalone app). You actually don't even need it necessarily. it's only for people who were actively using the multi-agent manager. I saw numerous people claiming that the IDE was gone, or that it was nuked to have no agentic sidebar anymore. It's still there, I assure you, no downgrade needed. Google will block those attempts anyway, even if you manage to get it working initially.

Here's how you can get Antigravity IDE to be exactly how it was before the update, minus the open agent manager button on the top bar of the app, to the right side. (in my case the project was literally still open like it'd never even updated, after i did the following steps)

1. Wipe the Conflict/Uninstall Both Antigravity (2.0) and Antigravity IDE (using Windows Settings)

1. Close all Antigravity windows completely.
2. Go to Windows Settings > Apps > Installed apps. (I don't recommend using a 3rd party uninstaller like Revo as it may try to delete extra leftover files, like your chat history and needed project files.)
3. Uninstall both "Antigravity" and "Antigravity IDE" to clear the hijacked system paths. (Your actual project code files/prompt history/artifacts/etc are 100% safe).

2. Install the latest Antigravity IDE First (Most Important Step)

1. Go to antigravity.google/product/antigravity-ide and download the Windows x64 installer.
2. Run it to lock in the proper editor system shortcuts (the black icon).
3. Open the IDE once so it builds its fresh user profile directories, then close it.

3. Sync Your Extensions & Chat History

Because Google changed the folder names for the split apps, fresh installs look completely blank. Open a standard Windows Command Prompt (CMD)—not PowerShell (powershell expects full file paths without %APPDATA% if you want to go that route) —and run these two commands to clone your data over:

DOS

xcopy /E /H /Y /I "%APPDATA%\Antigravity" "%APPDATA%\Antigravity IDE"

DOS

xcopy /E /H /Y /I "%USERPROFILE%\.gemini\antigravity" "%USERPROFILE%\.gemini\antigravity-ide"

4. Install 2.0 Last

1. Download (https://storage.googleapis.com/antigravity-public/antigravity-hub/2.0.0-6324554176528384/windows-x64/Antigravity.exe) and Run the installer for the standalone Antigravity 2.0 app (the white icon).
2. Because the IDE already claimed its system paths, 2.0 will now install cleanly on its own parallel track without hijacking your editor launcher.

The Result

The Antigravity IDE gives you back your full traditional editor layout with the integrated agent sidebar, and the Antigravity 2.0 app sits in the background as your high-level multi-agent dashboard (only if needed). No Google is not gutting functionality, they just figured people would rather have a persistent Agent Manager in a separate window with slightly better UI that you don't have to click a button in the IDE to open. Not really a huge change. The new models are pretty awesome though.

🚨 UPDATE: Getting "Agent Execution Terminated Due To Error/HTTP 429/Resource Exhausted" after the initial fix?

If you successfully applied the initial update fix but all your models are now throwing "HTTP 429 Too Many Requests" or "RESOURCE_EXHAUSTED" errors, a corrupted config file is causing it.

🔍 Why it happens:

The initial update fix can leave a completely empty (0-byte) configuration file. The IDE gets stuck in an infinite crash-and-restart loop trying to read this blank file, which floods Google's backend with requests and temporarily blacklists your connection.

🛠️ How to fix it:

1. Open the Config File

**Windows Users:** Press the **Windows Key + R** on your keyboard, paste the following line, and click **OK**:

notepad %USERPROFILE%\.gemini\config\mcp_config.json

**Mac Users:** Open your **Terminal** app, paste the following line, and press **Enter**:

open -e ~/.gemini/config/mcp_config.json

2. Fix the File

* The file will open up in Notepad or TextEdit. It will likely be completely empty.

* Type exactly this: {}

* Save the file and close the editor.

3. Restart your IDE. Don't do anything else. Just confirm it opens normally without trying any prompts. Close Antigravity IDE completely. Leave it closed for now. While the IDE is left open, the language server automatically runs a background status poll every 5 minutes like clockwork to verify your login state and refresh available models. This will just keep resetting the 429 wait time to be unblocked.

4. ⏳ CRITICAL: Wait 1 hour before trying any prompts, for any models. (I know it's long, and it's typically 15 minutes to stop 429 errors, but Google seems to be heavily restricting this right now because everyone's is repeatedly looping at once, overloading their servers. I'll update this if I can confirm it's back to 15 minutes, even it means forcing the error again to test lol)

Even though your IDE is no longer crashing, Google's backend still has your connection blocked.

Do NOT send any prompts or chat messages in the IDE for a full hour

If you NEED to do work immediately, do all prompts in the new Antigravity standalone app with the Antigravity IDE open too for now. It communicates with a completely different multi-agent, higher capacity server and should be working fine. Mine says this when asked:

"💡 Your Real-Time Workaround: Let me do the coding!

You don't have to wait around to write code! Since this main chat application uses a completely different API channel with higher capacity, I am not blocked at all."