# How to Install Google Agent Skills Plugins: CLI Commands for Claude Code, Codex, and Antigravity

> Install Google Agent Skills plugins like Claude Code, Codex, and Antigravity with simple CLI commands after adding the google/skills repository. Get started today.

- Repository: [Google/skills](https://github.com/google/skills)
- Tags: how-to-guide
- Published: 2026-09-04

---

**Google Agent Skills plugins are installed via harness-specific CLI commands after adding the google/skills repository with `npx skills add google/skills`.**

The `google/skills` repository hosts open-source agent capabilities packaged as plugins for large language model (LLM) agent harnesses. Understanding the correct **installation commands for Google Agent Skills plugins** ensures seamless integration with your preferred development environment, whether you use Claude Code, Codex, or Antigravity CLI.

## Prerequisites

Before installing individual plugins, you must register the entire skills catalog with your environment. According to the source code in [`README.md`](https://github.com/google/skills/blob/main/README.md), run the following global command:

```bash
npx skills add google/skills

```

This command pulls the full catalog of available skills into your workflow, enabling subsequent plugin-specific installations.

## Installation Commands by Agent Harness

Each LLM agent harness implements its own plugin management interface. The **installation commands for Google Agent Skills plugins** vary depending on your target platform as documented in the repository's installation table (lines 81-85 of [`README.md`](https://github.com/google/skills/blob/main/README.md)).

### Claude Code

For Anthropic's Claude Code agent, you must first add the Google Skills marketplace, then install specific plugins using the `@google-plugins` namespace.

Execute these commands in your terminal:

```bash

# Add the Google Skills marketplace

claude plugin marketplace add google/skills

# Install a specific plugin (replace <plugin> with the skill name)

claude plugin install <plugin>@google-plugins

```

For example, to install the **google-cloud-recipe-onboarding** plugin:

```bash
claude plugin install google-cloud-recipe-onboarding@google-plugins

```

### Codex

OpenAI's Codex agent requires marketplace registration followed by UI-based selection. First, run the CLI command to add the marketplace:

```bash
codex plugin marketplace add google/skills

```

Then open the `/plugins` browser interface within Codex and select the desired plugin from the Google Skills catalog to complete installation.

### Antigravity CLI

The Antigravity CLI (agy) supports direct URL-based installation without marketplace registration. Install plugins by specifying the full GitHub path to the skill directory:

```bash
agy plugin install https://github.com/google/skills/<plugin-path>

```

For instance, to install the **google-cloud-recipe-onboarding** skill located at `skills/cloud/google-cloud-recipe-onboarding`:

```bash
agy plugin install https://github.com/google/skills/skills/cloud/google-cloud-recipe-onboarding

```

## Source Files and Skill Definitions

The installation instructions are maintained in **[`README.md`](https://github.com/google/skills/blob/main/README.md)** at the repository root, specifically around lines 81-85 where the harness-specific tables reside. Individual skill definitions, including configuration and documentation, are stored in dedicated directories such as [`skills/cloud/google-cloud-recipe-onboarding/SKILL.md`](https://github.com/google/skills/blob/main/skills/cloud/google-cloud-recipe-onboarding/SKILL.md).

## Summary

- **Initialize the catalog** with `npx skills add google/skills` before installing individual plugins
- **Claude Code** uses marketplace registration followed by `claude plugin install <name>@google-plugins`
- **Codex** requires `codex plugin marketplace add google/skills` then UI selection via `/plugins`
- **Antigravity CLI** installs directly from GitHub URLs using `agy plugin install` with the full repository path
- All installation methods reference the `google/skills` repository as the source of truth

## Frequently Asked Questions

### What is the prerequisite command for all Google Agent Skills installations?

You must first run `npx skills add google/skills` to register the repository with your environment. This command applies universally across Claude Code, Codex, and Antigravity CLI workflows before harness-specific plugin installation.

### How do I install a specific plugin in Claude Code?

First add the marketplace with `claude plugin marketplace add google/skills`, then install using the plugin name suffixed with `@google-plugins`. For example: `claude plugin install google-cloud-recipe-onboarding@google-plugins`.

### Can I install Google Agent Skills plugins without using marketplace commands?

Yes, if you use Antigravity CLI. Instead of marketplace registration, execute `agy plugin install` followed by the complete GitHub URL to the skill directory, such as `https://github.com/google/skills/skills/cloud/google-cloud-recipe-onboarding`.

### Where are the skill definitions stored in the repository?

Each skill's core documentation and configuration reside in individual directories under the `skills/` path. For example, the **google-cloud-recipe-onboarding** skill definition is located at [`skills/cloud/google-cloud-recipe-onboarding/SKILL.md`](https://github.com/google/skills/blob/main/skills/cloud/google-cloud-recipe-onboarding/SKILL.md) within the `google/skills` repository.