Claude Code Via Antigravity

Claude Code Free

**Use [Claude Code](https://docs.anthropic.com/en/docs/claude-code) CLI for free** through Google's Antigravity (Cloud Code Assist) subscription.

A lightweight local proxy that bridges Claude Code CLI ↔ Google Cloud Code Assist API, giving you access to **Claude Opus 4.6** and **Claude Sonnet 4.5** — no Anthropic API key needed.

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How It Works

┌──────────────┐     ┌─────────────────┐     ┌──────────────────────────┐
│  Claude Code  │────▶│  Local Proxy     │────▶│  Google Cloud Code Assist│
│  CLI          │◀────│  (localhost:51200)│◀────│  (Antigravity API)       │
└──────────────┘     └─────────────────┘     └──────────────────────────┘
   Anthropic API         Translates             Has Claude models via
   format                formats                Google subscription

The proxy intercepts Claude Code CLI requests, translates them from Anthropic's format to Google's Cloud Code Assist API, and returns the responses in the format Claude Code expects. This works because Google's Antigravity/Code Assist subscription includes access to Claude models.

Prerequisites

• Node.js 18+ — Download
• Claude Code CLI — npm install -g @anthropic-ai/claude-code
• Google Account with Antigravity IDE Ultra or Google One AI Premium subscription

Quick Start

1. Clone the repo

git clone https://github.com/SovranAMR/claude-code-via-antigravity.git
cd claude-code-via-antigravity

2. Authenticate with Google

node setup.mjs login

This opens your browser for Google OAuth. Sign in with the account that has the Antigravity/AI Premium subscription.

3. Launch Claude Code

**Linux / macOS:**

./start.sh

**Windows (PowerShell):**

.\start.ps1

**Windows (double-click):** Just double-click `start.bat`

That's it! Claude Code CLI opens with fu