How to Install Google Skills for Antigravity CLI: A Complete Guide

You install Google Skills for the Antigravity CLI by running agy plugin install followed by the direct repository URL to the specific plugin submodule, such as agy plugin install https://github.com/google/skills/plugins/cloud/data-agent-kit/alloydb.

The google/skills repository hosts a centralized collection of Markdown-based skills and optional MCP (Model Context Protocol) servers that extend the Antigravity CLI (agy) with product-specific commands. Unlike marketplace-driven assistants, Antigravity pulls plugins directly from Git submodules, allowing you to install only the capabilities you need without downloading the entire repository.

Understanding the Antigravity Plugin Architecture

The Antigravity CLI (agy) does not use a centralized marketplace manifest like Claude Code or Codex. Instead, it clones plugin code directly from repository URLs.

When you execute agy plugin install, the CLI:

1. Clones the requested submodule path (e.g., plugins/cloud/data-agent-kit/alloydb)
2. Reads the plugin.json metadata file located at the root of that plugin directory
3. Registers the skill definitions and MCP configurations for the current session

This architecture is defined in the repository's .gitmodules file, which maps each plugin to a specific commit tag for deterministic versioning.

Prerequisites

Before installing Google Skills, ensure you have the Antigravity CLI installed and accessible via the agy command.

Optionally, to browse the full skill catalog locally, install the top-level skills package:

npx skills add google/skills

This command pulls the repository's main README and plugin index, though it is not required to run individual skill commands.

Installing Individual Google Skill Plugins

To add a specific capability—such as database management or cloud resource orchestration—you install plugins individually by targeting their submodule path.

Installing the AlloyDB Plugin

The AlloyDB plugin provides commands for managing AlloyDB clusters and instances. To install it from the google/skills repository:

agy plugin install https://github.com/google/skills/plugins/cloud/data-agent-kit/alloydb

After installation, verify the plugin loads correctly:

agy list          # Confirms 'alloydb' appears in installed plugins

agy help alloydb  # Displays available AlloyDB-specific commands

Installing the Spanner Plugin

Similarly, install the Cloud Spanner plugin to enable SQL query execution and schema management:

agy plugin install https://github.com/google/skills/plugins/cloud/data-agent-kit/spanner

Once registered, you can execute Spanner commands directly:

agy spanner query "SELECT * FROM my_database.my_table LIMIT 10"

Available Plugin Paths

Each plugin resides under plugins/cloud/data-agent-kit/<plugin-name>/ within the repository. The plugin.json file inside each directory defines the plugin's entry points and version metadata consumed by Antigravity.

Verifying Plugin Installation

After running the install command, Antigravity immediately makes the skill available in your current session. Validate the installation by listing registered plugins or invoking help for the specific skill:

# List all active plugins

agy list

# Get help for a specific Google Skill

agy help spanner

Updating and Managing Plugins

Because Antigravity treats each plugin as an isolated repository path, you control versions through Git submodules. To upgrade a plugin:

1. Check the .gitmodules file in the google/skills repository to identify the latest tagged version
2. Re-run the agy plugin install command with the updated URL or tag

This submodule-based approach ensures that agy always pulls the exact code specified in the central repository, preventing version drift across your CLI environment.

Summary

• Direct URL installation: Antigravity installs Google Skills via agy plugin install <URL> rather than a package manager or marketplace.
• Submodule structure: Plugins are stored under plugins/cloud/data-agent-kit/<name>/ and tracked as Git submodules in .gitmodules.
• Metadata discovery: Each plugin contains a plugin.json that Antigravity reads to register commands and MCP servers.
• Granular control: Install only the plugins you need (e.g., AlloyDB, Spanner) without cloning the entire google/skills repository.
• Immediate availability: Skills are active immediately after installation and persist for the current CLI session.

Frequently Asked Questions

Do I need to clone the entire google/skills repository to use a plugin?

No. The Antigravity CLI clones only the specific submodule path you provide in the agy plugin install command. You do not need to manually clone the repository or download the full skill catalog to use individual plugins.

Where does Antigravity find the command definitions for a skill?

Antigravity reads the plugin.json file located at the root of each plugin directory (e.g., plugins/cloud/data-agent-kit/alloydb/plugin.json). This JSON file defines the plugin name, version, entry points, and available commands that the CLI registers.

How do I upgrade an installed Google Skill to the latest version?

Upgrade a plugin by re-running the agy plugin install command with the updated URL or tag. The google/skills repository uses Git submodules (defined in .gitmodules) to pin plugins to specific versions, so updating your local reference and reinstalling pulls the latest code.

Can I use Google Skills without the Antigravity CLI?

The google/skills repository also supports the npx skills add command for browsing documentation, but the interactive commands and MCP integrations require the Antigravity CLI (agy). The skills are designed specifically to extend the agy command set with product-aware operations.

{
  "mcpServers": {
    "instagit": {
      "command": "npx",
      "args": ["-y", "instagit@latest"]
    }
  }
}