# Antigravity Login Issue on MacBook & How I Finally Fixed It (After Hours of Trying)

## **The Problem**

If you're reading this, you're probably stuck in the same nightmare I was: Antigravity shows **"Authentication Required Please sign in"** no matter what you do. You've reinstalled it. You've cleared the browser cache. You've restarted your MacBook. Nothing works.

![](https://cdn.hashnode.com/uploads/covers/63f0aa570e63a77a616fd5ab/c2f42a03-6a43-41a6-855d-0e5820562c61.png align="center")

Here's the complete story of what happened, every fix I tried, and what finally resolved it.

**The symptoms were confusing and contradictory:**

*   Antigravity's **Settings page showed my Google account**, so it knew I was logged in
    
*   But the **main/Agent view kept showing "Sign In"**
    
*   Clicking "Sign In" would open Google auth in the browser, I'd complete it successfully, but Antigravity would **loop right back** to "Authentication Required"
    
*   I couldn't even **sign out**, there was no sign-out option because the app was in a broken half-authenticated state
    

## **What I Already Tried (That Didn't Work)**

Before finding the real fix, I tried everything the internet suggested:

*   ❌ Restarted the MacBook
    
*   ❌ Cleared browser cache and cookies
    
*   ❌ Deleted Antigravity and reinstalled it
    
*   ❌ Deleted `~/Library/Application Support/Antigravity/Session Storage`
    
*   ❌ Deleted `~/Library/Application Support/Antigravity/Local Storage`
    
*   ❌ Deleted `auth-tokens`, `Cookies` folders
    
*   ❌ Deleted `~/.gemini/antigravity`
    
*   ❌ Used `Ctrl+Shift+P` → `Antigravity: Reset Onboarding`
    
*   ❌ Applied the BigInt patch to `main.js`
    
*   ❌ Switched default browser from Brave to Safari
    

**None of it worked.** Here's why, I was missing the actual root cause every single time.

## **The Root Cause: macOS Keychain**

Here's what nobody tells you:

When Antigravity first authenticates, it stores an encrypted token in **macOS Keychain** under the name **"Antigravity Safe Storage"**. This is completely separate from the app's files in `~/Library/Application Support/`.

When you **uninstall** Antigravity, the app files are removed, but the Keychain entry **stays behind**. When you reinstall and try to log in again, Antigravity finds this old, expired, corrupted token in Keychain and tries to use it. It fails silently. No error message. Just "Authentication Required" forever.

**This is why:**

*   Other macOS user profiles on the same Mac worked fine (each profile has its own Keychain)
    
*   Reinstalling never helped (Keychain survives uninstalls)
    
*   Clearing Library folders never helped (Keychain is stored separately)
    

## **The Fix**

### **Step 1: Kill Antigravity completely**

```plaintext
pkill -f Antigravity
```

### **Step 2: Delete all app data**

```plaintext
rm -rf ~/Library/Application\ Support/Antigravity/
rm -rf ~/.gemini/antigravity
rm -rf ~/Library/Caches/Antigravity/
rm -rf ~/Library/Logs/Antigravity/
```

### **Step 3: Delete the Keychain entry (THE KEY STEP)**

```shell
security delete-generic-password -l "Antigravity Safe Storage"
```

**You should see:**

```shell
password has been deleted.
```

Alternatively, do it via UI:

1.  Open **Keychain Access** (Spotlight → search "Keychain Access")
    
2.  Search for `antigravity`
    
3.  Right-click **"Antigravity Safe Storage"** → Delete
    
4.  Enter your Mac login password when prompted → click **Always Allow**
    

### **Step 4: Set Safari as default browser temporarily**

*   Apple menu → **System Settings** → **Desktop & Dock** → **Default web browser** → **Safari**
    
    > **Why Safari? If you use Brave, its aggressive "Auto-redirect tracking URLs" feature intercepts the OAuth callback URL and silently kills the token handoff back to the app.**
    

### **Step 5: Sign in**

1.  Open Antigravity
    
2.  Click **Sign In**
    
3.  Complete Google auth in Safari
    
4.  ✅ Done, switch back to Brave after
    

![](https://cdn.hashnode.com/uploads/covers/63f0aa570e63a77a616fd5ab/0b6e85d7-5ff0-4b03-9be3-70d0dc5b9094.png align="center")

### **Bonus: Why Brave Browser Made It Worse**

Even after fixing the Keychain issue, if you use Brave as your default browser, you may still face the auth loop. Brave's Shields intercept OAuth redirect URLs as "tracking URLs" and kill the token handoff. The fix is simple, use Safari (or any non-Brave browser) as your default browser just for the sign-in step.

## **Conclusion**

| **What I tried** | **Why it failed** |
| --- | --- |
| Reinstalling Antigravity | Keychain token survives uninstalls |
| Clearing Library folders | Keychain is stored separately |
| BigInt patch | Different issue entirely |
| Browser cache clear | OAuth token lives in Keychain, not browser |
| **Deleting Keychain entry** | ✅ This was the actual fix |

The corrupted Keychain entry in my case was dated **November 21, 2025**. A 4-month-old stale token that had been silently blocking every login attempt since then.

If you're stuck on this issue, go straight to the Keychain step. It'll save you hours.