1. Background

Antigravity IDE is built on an Electron architecture, and its AI capabilities depend on the Google Cloud Code Assist backend.

Many users on Windows run into this:

• The browser can reach Google
• Antigravity works once the VPN is in TUN mode
• After turning TUN off:
  • Login fails
  • The AI chat window cannot connect
  • The model list fails to load

For example:

Language Server:
failed to get model infos from API server

oauth2.googleapis.com/token

connectex:
A connection attempt failed

The reason:

Not all network requests from Antigravity are made by the main process.

The actual structure:

Antigravity.exe
        |
        |
        +---- Electron UI
        |
        +---- language_server.exe
                    |
                    |
                    +---- Google Code Assist API
                    |
                    +---- OAuth API

The ones that actually reach:

oauth2.googleapis.com

daily-cloudcode-pa.googleapis.com

cloudcode-pa.googleapis.com

are:

language_server.exe

So:

Proxying only:

Antigravity.exe

is not enough.

---

2. The Approach

The traditional approach:

Windows
 |
VPN
 |
TUN mode
 |
All traffic proxied

Drawbacks:

• Domestic Chinese sites also go through the proxy
• Games are affected
• Latency increases
• DNS changes

This tutorial’s approach:

Antigravity.exe
        |
        |
ProxyBridge
        |
        |
SOCKS5 proxy
        |
        |
Clash / sing-box / v2ray

Only Antigravity goes through the proxy.

Other software:

Browser
Games
WeChat
Download tools

↓

Direct connection

---

3. Preparation

1. Prepare a SOCKS5 proxy

You need a local SOCKS5 service.

For example:

Clash:

Open:

Settings

Enable:

Socks Port

For example:

127.0.0.1:7890

Or:

sing-box:

127.0.0.1:1080

Test:

CMD:

curl --socks5 127.0.0.1:7890 https://www.google.com

As long as it returns content, you are good.

---

4. Install ProxyBridge

Project URL:

https://github.com/InterceptSuite/ProxyBridge

Go to:

Releases

Download the Windows version.

After installing:

Recommended:

Right-click:

ProxyBridge.exe

↓

Run as Administrator

Reason:

ProxyBridge depends internally on:

WinDivert

which requires administrator privileges.

---

5. Configure the Proxy

Open ProxyBridge.

Go to:

Proxy Settings

Add:

Type:

SOCKS5

Address:

127.0.0.1

Port:

10808

For example:

Protocol:

SOCKS5


Host:

127.0.0.1


Port:

10808

Save.

---

6. Find the Antigravity Subprocess

This is the most critical step.

Open:

Task Manager

Go to:

Details

Start Antigravity.

You will see:

Antigravity.exe

language_server_windows_x64.exe

right-click Properties and find the exact directories of these two processes

Key point:

You must proxy language_server_windows_x64.exe, otherwise: AI chat will still fail.

---

7. Add a ProxyBridge Rule

Go to:

Proxy Rules

↓

Add Rule

In Applications, enter the full directory, e.g. C:\Users\xxxx\AppData\Local\Programs\Antigravity IDE. Note that both file names must be entered.

---

8. Restart Antigravity

Exit completely:

Do not just close the window.

Confirm in Task Manager:

Antigravity.exe

language_server.exe

all ended.

Reopen it.

---

9. Verify Success

Method 1: Check the ProxyBridge Log

You should see:

language_server.exe

CONNECT

oauth2.googleapis.com:443

PROXY

If you see:

DIRECT

it means no rule matched.

---

Method 2: Check the AI Chat

Signs of success:

Before:

Failed to get model infos

loadCodeAssist failed

becomes:

loadCodeAssist success

Then:

• The model list appears
• AI Chat works
• Gemini replies normally

---

10. Common Issues

1. Login succeeds but AI chat fails

Reason:

Only this was proxied:

Antigravity.exe

Fix:

Add:

language_server.exe

---

2. Cannot find language_server.exe

Search:

Windows File Explorer:

language_server.exe

Or:

PowerShell:

Get-Process | findstr Antigravity

---

3. Google OAuth fails

Add proxy rules:

accounts.google.com

oauth2.googleapis.com

*.googleapis.com

*.cloudcode-pa.googleapis.com

---

4. Updates fail

Add:

updater.exe

to the proxy.

---

11. Why Not Use TUN?

TUN:

Entire Windows network
        |
        |
       VPN

ProxyBridge:

Specified process
        |
        |
       VPN proxy

Advantages: