Antigravity MCP Server & OpenAI-Compatible API Bridge

This project provides a Dual-Mode Integration solution for Google Antigravity:

1. OpenAI-Compatible REST API Bridge (server.js): A local HTTP REST API server (http://localhost:8088/v1) that enables WhatsApp bots, Node.js scripts, Python clients, or any external application using the openai SDK (const { OpenAI } = require('openai')) to communicate with Antigravity models and automatically integrate with real-time Widyartha database context.

2. MCP Stdio Server (index.js): A local Model Context Protocol (Stdio) server for registering local tools directly inside the Antigravity IDE UI without requiring external API keys.

🛠️ Key Features

• OpenAI SDK Integration: Seamlessly use standard openai libraries by redirecting baseURL to http://localhost:8088/v1.

• Real-Time MCP Data Integration: The HTTP server automatically enriches AI completion prompts with product catalog stock, order status, and invoice information from the local Widyartha SQLite database.

• Comprehensive Model Selection: Supports model presets matching the Antigravity IDE UI dropdown:

  • gemini-3.6-flash-high, gemini-3.6-flash-medium, gemini-3.6-flash-low

  • gemini-3.5-flash-high, gemini-3.5-flash-medium, gemini-3.5-flash-low

  • gemini-3.1-pro-high, gemini-3.1-pro-low

  • claude-sonnet-4.6, claude-opus-4.6

  • gpt-oss-120b, antigravity

• Auto-Setup & Portable: Automatically generates local security tokens, auto-installs missing dependencies, and uses relative paths for full portability across drives/folders.

Related MCP server: codex-web-bridge

🚀 Running the API Server

1. Start the HTTP Server (Port 8088)

Run the following command in your terminal:

npm start

Or double-click start-server.bat (Windows) / start-server.sh (Linux/macOS).

The server will listen at:

• Base URL: http://localhost:8088/v1

• Chat Completion: POST http://localhost:8088/v1/chat/completions

• List Models: GET http://localhost:8088/v1/models

💻 Client Usage Examples (Node.js & Python)

Node.js Example:

const { OpenAI } = require('openai');

const openai = new OpenAI({
  apiKey: 'sk-random-key',
  baseURL: 'http://localhost:8088/v1'
});

async function main() {
  const response = await openai.chat.completions.create({
    model: 'antigravity',
    messages: [
      { role: 'user', content: 'Check batik shirt stock' }
    ]
  });

  console.log(response.choices[0].message.content);
}

main();

Python Example:

from openai import OpenAI

client = OpenAI(
    api_key="sk-random-key",
    base_url="http://localhost:8088/v1"
)

response = client.chat.completions.create(
    model="antigravity",
    messages=[
        {"role": "user", "content": "Check batik shirt stock"}
    ]
)

print(response.choices[0].message.content)

📋 Installing MCP Server in Antigravity IDE UI

To register the MCP Server directly in the Antigravity IDE UI:

1. Open the Customizations panel in Antigravity IDE.

2. Click the Open MCP Config button.

3. Paste the following JSON configuration:

{
  "mcpServers": {
    "antigravity-mcp": {
      "command": "node",
      "args": [
        "E:/code/ai-bot-cs/MCP/antigravity/index.js"
      ],
      "cwd": "E:/code/ai-bot-cs/MCP/antigravity"
    }
  }
}

4. Save the file and click Refresh 🔄.

🧪 Testing (Test Scripts)

All test scripts are located inside the test/ directory:

• Run Node.js OpenAI SDK Test:

  npm test

  (Executes node test/client-example.js)

• Run Python OpenAI Client Test:

  npm run test:python
  # Or: python test/test_openai_client.py

• Run MCP Stdio Protocol Test:

  npm run test:mcp
  # Or: python test/check_mcp.py

📁 Directory Structure

E:\code\ai-bot-cs\MCP\antigravity\
├── server.js              # OpenAI Bridge HTTP REST API Server (Port 8088)
├── index.js               # MCP Stdio Server for Antigravity IDE UI
├── mcp-config.json        # Antigravity MCP Configuration Template
├── start-server.bat       # Portable Windows Launcher (Auto npm install)
├── start-server.sh        # Portable Linux/macOS Launcher
├── .env & .env.example    # Environment Variables
├── .gitignore             # Git Ignore Rules
├── package.json           # Package Manifest & Scripts
├── README.md              # English Documentation
└── test/                  # Test Scripts Directory
    ├── client-example.js     # Node.js OpenAI Client Test
    ├── test_openai_client.py # Python OpenAI Client Test
    └── check_mcp.py          # MCP Stdio Protocol Test