A production-grade VS Code extension that integrates custom language models into the native Copilot Chat experience via the official Language Model Chat Provider API.

Features

Native Integration: Use custom models directly within VS Code's Copilot Chat (@antigravity).
Reasoning Effort Levels & Gemini 3.6: Full support for new Antigravity models (Gemini 3.6 Flash, Gemini 3.5 Flash, Gemini 3.1 Pro, Claude 4.6, GPT-OSS 120B) and reasoning effort levels (Low, Medium, High).
BYOK Auto-Fix: Automatically configures VS Code's utility models to prevent "No utility model configured" errors when using Bring Your Own Key (BYOK) providers.
Customizable Models: Choose your primary model for code generation and a lightweight model for background tasks.
Dashboard UI: View the status of your local proxy and available models.
Streaming Support: Enjoy real-time streaming responses in Copilot Chat.

Installation

Download the .vsix package from the releases page.
Open VS Code.
Go to the Extensions view (Ctrl+Shift+X or Cmd+Shift+X).
Click the ... menu in the top right of the Extensions view.
Select Install from VSIX...
Choose the downloaded .vsix file.

Configuration

Configure the extension by navigating to Settings (Ctrl+, or Cmd+,) and searching for Antigravity Copilot.

Available Settings

antigravityCopilot.defaultModel: Primary model for chat conversations and code generation.
antigravityCopilot.utilityModel: Lightweight model for background Copilot utility tasks (title generation, summaries). Choose a faster/cheaper model here.
antigravityCopilot.backendUrl: Base URL of the local proxy API server.
antigravityCopilot.cliPath: Path to the Antigravity CLI executable.
antigravityCopilot.streaming.enabled: Enable streaming responses.
antigravityCopilot.temperature: Sampling temperature for model responses.
antigravityCopilot.maxOutputTokens: Maximum number of tokens in the model response.
antigravityCopilot.logging.level: Logging verbosity level (debug, info, warn, error).
antigravityCopilot.logging.verbose: Enable verbose mode to log request/response payloads.

BYOK Utility Model Fix

When using a custom model as your primary Copilot agent, VS Code requires a utility model for background tasks. This extension automatically configures the necessary settings (github.copilot.chat.byokUtilityModelDefault, chat.utilityModel, chat.utilitySmallModel) based on your antigravityCopilot.utilityModel selection.