docs: add Learning Hub article on installing and using plugins

- New article covering plugin concepts, finding/installing/managing plugins,
  marketplace browsing, and how this repo serves as a plugin marketplace
- Add 'installing-and-using-plugins' to fundamentalsOrder in index.astro
  and ArticleLayout.astro
- Add Plugin entry to terminology glossary

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

website/src/content/learning-hub/github-copilot-terminology-glossary.md

@@ -215,6 +215,20 @@ The autonomous GitHub Copilot agent that works on issues in a cloud environment
 
 ---
 
+### Plugin
+
+An installable package that extends GitHub Copilot CLI with a bundled set of agents, skills, hooks, MCP server configurations, and LSP integrations. Plugins provide a way to distribute and share custom capabilities across projects and teams, with versioning, discovery, and one-command installation via marketplaces.
+
+**Example**: Installing `database-data-management@awesome-copilot` to get a database specialist agent, migration skills, and schema validation hooks in a single command.
+
+**When to use**: When you want to share a curated set of Copilot capabilities across multiple projects or team members, or when you want to install community-contributed tooling without manually copying files.
+
+**Learn more**: [Installing and Using Plugins](/learning-hub/installing-and-using-plugins/)
+
+**Related terms**: [Agent](#agent), [Skill](#skill), [Hook](#hook)
+
+---
+
 ### Tools
 
 Capabilities that GitHub Copilot can invoke to perform actions or retrieve information. Tools fall into two categories:

website/src/content/learning-hub/installing-and-using-plugins.md

@@ -0,0 +1,249 @@
+---
+title: 'Installing and Using Plugins'
+description: 'Learn how to find, install, and manage plugins that extend GitHub Copilot CLI with reusable agents, skills, hooks, and integrations.'
+authors:
+  - GitHub Copilot Learning Hub Team
+lastUpdated: '2026-02-26'
+estimatedReadingTime: '8 minutes'
+tags:
+  - plugins
+  - copilot-cli
+  - fundamentals
+relatedArticles:
+  - ./building-custom-agents.md
+  - ./creating-effective-skills.md
+  - ./automating-with-hooks.md
+prerequisites:
+  - GitHub Copilot CLI installed
+  - Basic understanding of agents, skills, and hooks
+---
+
+Plugins are installable packages that extend GitHub Copilot CLI with reusable agents, skills, hooks, and servers, all bundled into a single unit you can install with one command. Instead of manually copying agent files and configuring MCP servers across every project, plugins let you install a curated set of capabilities and share them with your team.
+
+This article explains what plugins contain, how to find and install them, and how to manage your plugin library.
+
+## What's Inside a Plugin?
+
+A plugin bundles one or more of the following components:
+
+| Component | What It Does | File Location |
+|-----------|-------------|---------------|
+| **Custom Agents** | Specialized AI assistants with tailored expertise | `agents/*.agent.md` |
+| **Skills** | Discrete callable capabilities with bundled resources | `skills/*/SKILL.md` |
+| **Hooks** | Event handlers that intercept agent behavior | `hooks.json` or `hooks/` |
+| **MCP Servers** | Model Context Protocol integrations for external tools | `.mcp.json` or `.github/mcp.json` |
+| **LSP Servers** | Language Server Protocol integrations | `lsp.json` or `.github/lsp.json` |
+
+A plugin might include all of these or just one — for example, a plugin could provide a single specialized agent, or an entire development toolkit with multiple agents, skills, hooks, and MCP server configurations working together.
+
+### Example: What a Plugin Looks Like
+
+Here's the structure of a typical plugin:
+
+```
+my-plugin/
+├── .github/
+│   └── plugin/
+│       └── plugin.json        # Plugin manifest (name, description, version)
+├── agents/
+│   ├── api-architect.agent.md
+│   └── test-specialist.agent.md
+├── skills/
+│   └── database-migrations/
+│       ├── SKILL.md
+│       └── scripts/migrate.sh
+├── hooks.json
+└── README.md
+```
+
+The `plugin.json` manifest declares what the plugin contains:
+
+```json
+{
+  "name": "my-plugin",
+  "description": "API development toolkit with specialized agents and migration skills",
+  "version": "1.0.0",
+  "agents": [
+    "./agents/api-architect.md",
+    "./agents/test-specialist.md"
+  ],
+  "skills": [
+    "./skills/database-migrations/"
+  ]
+}
+```
+
+## Why Use Plugins?
+
+You might wonder: why not just copy agent files into your project manually? Plugins provide several advantages:
+
+| Feature | Manual Configuration | Plugin |
+|---------|---------------------|--------|
+| **Scope** | Single repository | Any project |
+| **Sharing** | Manual copy/paste | `copilot plugin install` command |
+| **Versioning** | Git history | Marketplace versions |
+| **Discovery** | Searching repositories | Marketplace browsing |
+| **Updates** | Manual tracking | `copilot plugin update` |
+
+Plugins are especially valuable when you want to:
+
+- **Standardize across a team** — Everyone installs the same plugin for consistent tooling
+- **Share domain expertise** — Package a Rails expert, Kubernetes specialist, or security reviewer as an installable unit
+- **Encapsulate complex setups** — Bundle MCP server configurations that would otherwise require manual setup
+- **Reuse across projects** — Install the same capabilities in every project without duplicating files
+
+## Finding Plugins
+
+Plugins are collected in **marketplaces** — registries you can browse and install from. Copilot CLI comes with two marketplaces registered by default:
+
+- **`copilot-plugins`** — Official GitHub Copilot plugins
+- **`awesome-copilot`** — Community-contributed plugins from this repository
+
+### Browsing a Marketplace
+
+List your registered marketplaces:
+
+```bash
+copilot plugin marketplace list
+```
+
+Browse plugins in a specific marketplace:
+
+```bash
+copilot plugin marketplace browse awesome-copilot
+```
+
+Or from within an interactive Copilot session:
+
+```
+/plugin marketplace browse awesome-copilot
+```
+
+> **Tip**: You can also browse plugins on this site's [Plugins Directory](/plugins/) to see descriptions, included agents, and skills before installing.
+
+### Adding More Marketplaces
+
+Register additional marketplaces from GitHub repositories:
+
+```bash
+copilot plugin marketplace add anthropics/claude-code
+```
+
+Or from a local path:
+
+```bash
+copilot plugin marketplace add /path/to/local-marketplace
+```
+
+## Installing Plugins
+
+### From a Registered Marketplace
+
+The most common way to install a plugin — reference it by name and marketplace:
+
+```bash
+copilot plugin install database-data-management@awesome-copilot
+```
+
+Or from an interactive session:
+
+```
+/plugin install database-data-management@awesome-copilot
+```
+
+## Managing Plugins
+
+Once installed, plugins are managed with a few simple commands:
+
+```bash
+# List all installed plugins
+copilot plugin list
+
+# Update a plugin to the latest version
+copilot plugin update my-plugin
+
+# Remove a plugin
+copilot plugin uninstall my-plugin
+```
+
+### Where Plugins Are Stored
+
+- **Marketplace plugins**: `~/.copilot/installed-plugins/MARKETPLACE/PLUGIN-NAME/`
+- **Direct installs**: `~/.copilot/installed-plugins/_direct/PLUGIN-NAME/`
+
+## How Plugins Work at Runtime
+
+When you install a plugin, its components become available to Copilot CLI automatically:
+
+- **Agents** appear in your agent selection (use with `/agent` or the agents dropdown)
+- **Skills** are loaded automatically when relevant to your current task
+- **Hooks** run at the configured lifecycle events during agent sessions
+- **MCP servers** extend the tools available to agents
+
+You don't need to do any additional configuration after installing — the plugin's components integrate seamlessly into your workflow.
+
+## Plugins from This Repository
+
+This repository (`awesome-copilot`) serves as both a collection of individual resources _and_ a plugin marketplace. You can use it in two ways:
+
+### Install Individual Plugins
+
+Browse the [Plugins Directory](/plugins/) and install specific plugins:
+
+```bash
+copilot plugin install context-engineering@awesome-copilot
+copilot plugin install azure-cloud-development@awesome-copilot
+copilot plugin install frontend-web-dev@awesome-copilot
+```
+
+Each plugin bundles related agents and skills around a specific theme or technology.
+
+### Use Individual Resources Without Plugins
+
+If you only need a single agent or skill (rather than a full plugin), you can still copy individual files from this repo directly into your project:
+
+- Copy an `.agent.md` file into `.github/agents/`
+- Copy a skill folder into `.github/skills/`
+- Copy a hook configuration into `.github/hooks/`
+
+See [Using the Copilot Coding Agent](../learning-hub/using-copilot-coding-agent/) for details on this approach.
+
+## Best Practices
+
+- **Start with a marketplace plugin** before building your own — there may already be one that fits your needs
+- **Keep plugins focused** — a plugin for "Rails development" is better than a plugin for "everything"
+- **Check for updates regularly** — run `copilot plugin update` to get the latest improvements
+- **Review what you install** — plugins run code on your machine, so inspect unfamiliar plugins before installing
+- **Use plugins for team standards** — publish an internal plugin to ensure every team member has the same agents, skills, and hooks
+- **Remove unused plugins** — declutter with `copilot plugin uninstall` to keep your environment clean
+
+## Common Questions
+
+**Q: Do plugins work with the coding agent on GitHub.com?**
+
+A: Plugins are specific to GitHub Copilot CLI and the VS Code extension (currently Insiders). For the coding agent on GitHub.com, add agents, skills, and hooks directly to your repository (via a plugin if you prefer!). See [Using the Copilot Coding Agent](../learning-hub/using-copilot-coding-agent/) for details.
+
+**Q: Can I use plugins and repository-level configuration together?**
+
+A: Yes. Plugin components are merged with your repository's local agents, skills, and hooks. Local configuration takes precedence if there are conflicts.
+
+**Q: How do I create my own plugin?**
+
+A: Create a directory with a `plugin.json` manifest and your agents/skills/hooks. See the [GitHub docs on creating plugins](https://docs.github.com/en/copilot/how-tos/copilot-cli/customize-copilot/plugins-creating) for a step-by-step guide.
+
+**Q: Can I share plugins within my organization?**
+
+A: Yes. You can create a private plugin marketplace in an internal GitHub repository, then have team members register it with `copilot plugin marketplace add org/internal-plugins`.
+
+**Q: What happens if I uninstall a plugin?**
+
+A: The plugin's agents, skills, and hooks are removed from Copilot. Any work already done with those tools is unaffected — only future sessions lose access.
+
+## Next Steps
+
+- **Browse Plugins**: Explore the [Plugins Directory](/plugins/) for installable plugin packages
+- **Create Skills**: [Creating Effective Skills](../learning-hub/creating-effective-skills/) — Build skills that can be included in plugins
+- **Build Agents**: [Building Custom Agents](../learning-hub/building-custom-agents/) — Create agents to package in plugins
+- **Add Hooks**: [Automating with Hooks](../learning-hub/automating-with-hooks/) — Configure hooks for plugin automation
+
+---

website/src/layouts/ArticleLayout.astro

@@ -25,6 +25,7 @@ const fundamentalsOrder = [
   'understanding-mcp-servers',
   'automating-with-hooks',
   'using-copilot-coding-agent',
+  'installing-and-using-plugins',
   'before-after-customization-examples',
 ];
 

website/src/pages/learning-hub/index.astro

@@ -15,6 +15,7 @@ const fundamentalsOrder = [
   'understanding-mcp-servers',
   'automating-with-hooks',
   'using-copilot-coding-agent',
+  'installing-and-using-plugins',
   'before-after-customization-examples',
 ];