Antigravity Proxy

Antigravity Proxy is a high-performance gateway that exposes Google's internal Gemini and Claude APIs through an OpenAI-compatible interface. It enables seamless integration between advanced models (like Claude 4.6 Opus, Gemini 3, and GPT-equivalent models) and CLI agents (such as OpenCode or Claude Code), as well as any application supporting the OpenAI API standard.

This project is strongly inspired by opencode-antigravity-auth.

Features

• OpenAI API Compatibility: Full support for v1/chat/completions with streaming (SSE).
• Multi-Agent Support: Specifically designed to work with Claude Code, OpenCode, and other agentic frameworks.
• Account Rotation & Health Scoring: Automatically rotates multiple Google accounts, penalizing those with errors and favoring healthy ones.
• Quota Management: Real-time monitoring and automatic cooldowns (backoff) on 429 Too Many Requests errors.
• Dual-Pool Routing:
  • CLI Pool: Routes to production endpoints (Gemini 2.5/3 Flash & Pro).
  • Sandbox Pool: Accesses internal/experimental models (Claude 3.5 Sonnet, Thinking models, GPT-equivalent).
• Integrated Dashboard: Manage accounts, monitor health, and view real-time logs via a built-in web interface.
• Automatic Project Discovery: Auto-detects Google Cloud Project IDs via Cloud SDK impersonation.

Deployment Options

Bunx (Recommended)

You can run the proxy instantly using bunx:

bunx [email protected]

Docker Hub

docker run -d -p 3000:3000 -e BASE_URL=http://localhost:3000 --name antigravity-proxy frieserpaldi/antigravity-proxy:0.7.0

Local Execution (Bun)

Requirements: Bun (v1.0.0 or higher).

bun install
bun run start

The server starts on port 3000.

Integration Guides

Claude Code Configuration

To use Claude Code with Antigravity Proxy, point the API base URL to your local instance and specify a model from the Sandbox Pool:

# Point Claude Code to the proxy
export CLAUDE_CODE_API_BASE="http://localhost:3000/v1"

# Run Claude specifying an Antigravity model
claude --model antigravity-claude-sonnet-4-5

OpenCode Configuration

Add the following provider to your ~/.config/opencode/opencode.json under the "provider" key:

"provider": {
    "antigravity-proxy": {
        "npm": "@ai-sdk/openai-compatible",
        "name": "Antigravity Proxy",
        "options": {
            "baseURL": "http://localhost:3000/v1"
        },
        "models": {
            "antigravity-gemini-3.1-pro-low": {
                "name": "Gemini 3.1 Pro Low (Antigravity)",
                "limit": { "context": 1048576, "output": 65535 }
            },
            "antigravity-gemini-3.1-pro-high": {
                "name": "Gemini 3.1 Pro High (Antigravity)",
                "limit": { "context": 1048576, "output": 65535 }
            },
            "antigravity-gemini-3-pro-low": {
                "name": "Gemini 3 Pro Low (Antigravity)",
                "limit": { "context": 1048576, "output": 65535 }
            },
            "antigravity-gemini-3-pro-high": {
                "name": "Gemini 3 Pro High (Antigravity)",
                "limit": { "context": 1048576, "output": 65535 }
            },
            "antigravity-gemini-3-flash": {
                "name": "Gemini 3 Flash (Antigravity)",
                "limit": { "context": 1048576, "output": 65536 }
            },
            "antigravity-claude-sonnet-4-6": {
                "name": "Claude Sonnet 4.6 (Antigravity)",
                "limit": { "context": 200000, "output": 64000 }
            },
            "antigravity-claude-sonnet-4-6-thinking-low": {
                "name": "Claude Sonnet 4.6 Think Low (Antigravity)",
                "limit": { "context": 200000, "output": 64000 }
            },
            "antigravity-claude-sonnet-4-6-thinking-medium": {
                "name": "Claude Sonnet 4.6 Think Medium (Antigravity)",
                "limit": { "context": 200000, "output": 64000 }
            },
            "antigravity-claude-sonnet-4-6-thinking-high": {
                "name": "Claude Sonnet 4.6 Think High (Antigravity)",
                "limit": { "context": 200000, "output": 64000 }
            },
            "antigravity-claude-sonnet-4-5": {
                "name": "Claude Sonnet 4.5 (Antigravity)",
                "limit": { "context": 200000, "output": 64000 }
            },
            "antigravity-claude-sonnet-4-5-thinking-low": {
                "name": "Claude Sonnet 4.5 Think Low (Antigravity)",
                "limit": { "context": 200000, "output": 64000 }
            },
            "antigravity-claude-sonnet-4-5-thinking-medium": {
                "name": "Claude Sonnet 4.5 Think Medium (Antigravity)",
                "limit": { "context": 200000, "output": 64000 }
            },
            "antigravity-claude-sonnet-4-5-thinking-high": {
                "name": "Claude Sonnet 4.5 Think High (Antigravity)",
                "limit": { "context": 200000, "output": 64000 }
            },
            "antigravity-claude-opus-4-6-thinking-low": {
                "name": "Claude Opus 4.6 Think Low (Antigravity)",
                "limit": { "context": 1000000, "output": 64000 }
            },
            "antigravity-claude-opus-4-6-thinking-medium": {
                "name": "Claude Opus 4.6 Think Medium (Antigravity)",
                "limit": { "context": 1000000, "output": 64000 }
            },
            "antigravity-claude-opus-4-6-thinking-high": {
                "name": "Claude Opus 4.6 Think High (Antigravity)",
                "limit": { "context": 1000000, "output": 64000 }
            },
            "gemini-2.5-flash": {
                "name": "Gemini 2.5 Flash (CLI)",
                "limit": { "context": 1048576, "output": 65536 }
            },
            "gemini-2.5-pro": {
                "name": "Gemini 2.5 Pro (CLI)",
                "limit": { "context": 1048576, "output": 65536 }
            }
        }
    }
}

How It Works

Antigravity Proxy acts as a sophisticated bridge that translates OpenAI-formatted requests into Google's internal RPC protocols. It manages the complexities of authentication, session handling, and response streaming, allowing you to use high-tier models with your favorite tools.

Account Selection Strategy

• Hybrid (Default): Ranks accounts based on (Health Score × 2) + (Idle Time × 0.1).
• Sticky: Keeps a client session tied to the same account for consistency.
• Round-Robin: Cycles through all available accounts evenly.

Security Notes

• Safety Filters: Controlled via SAFETY_THRESHOLD (default: BLOCK_NONE).
• Credentials: OAuth tokens are stored locally in antigravity-accounts.json. Do not share or commit this file.