Antigravity Extensions (agy-extensions)

This skill provides step-by-step procedures, templates, configuration formats, and installation standards to author, deploy, and validate any custom extension for Antigravity CLI (AGY CLI) and Antigravity 2.0 (Desktop / IDE).

An Antigravity Extension can be authored and deployed in two ways:

1. Standalone Extensions: Individual capabilities installed directly into workspace or global configuration directories:
   • Skills (SKILL.md)
   • Rules (<rule-name>.md)
   • Custom Subagents (<agent-name>.md)
   • Event Hooks (hooks.json)
   • MCP Servers (mcp_config.json)
2. Bundled Plugins: A namespaced directory (plugins/<plugin-name>/) with a plugin.json manifest wrapper that bundles multiple extensions into a single package.

1. Quick Reference: Extension Target Locations Matrix

This table summarizes where to install standalone extensions and plugin bundles based on target scope and platform: