How to add a plugin or skill from GitHub

5 min read · Checked October 2026

The three ways tools get installed, plus how to add skills in the Claude app.

Most skills and plugins are shared on GitHub, a website where people publish code. You don’t need a GitHub account to install them. Each tool’s page on this site shows which of these routes to use and gives you the exact commands.

Route 1: install a plugin inside Claude Code

Most tools use this route. You type the commands inside Claude Code, not in the Terminal.

Add the collection the plugin comes from

Plugins live in collections called marketplaces. You add a collection once, using its GitHub name (owner and project). For example:

/plugin marketplace add thedotmack/claude-mem

Anthropic’s official collection is already added for you, so official plugins skip this step.

Install the plugin

/plugin install claude-mem@thedotmack

A panel opens with details about the plugin. Choose where to install it (“for you” works for everything on this site) and confirm.

Use it

Type / and look for skills starting with the plugin’s name, like /claude-mem:. Type /plugin any time to see, turn off or remove what you’ve installed.

Route 2: install a single skill from the Terminal

Some skills are shared on their own rather than in a plugin. These install with the skills installer, which you run in the Terminal (not inside Claude). For example:

npx skills add coreyhaines31/marketingskills --skill cro -g -a claude-code

This needs Node.js, a free program from nodejs.org. If the command says npx isn’t found, install Node.js first. Start a new Claude Code session afterwards and the skill is ready.

Route 3: add an agent from a template library

A few agents come from Claude Code Templates. Run the command from the tool’s page in the Terminal, inside your project folder:

npx claude-code-templates@latest --agent development-tools/code-reviewer --yes

In the Claude app instead

Skills also work in the Claude app (claude.ai and desktop), on any plan, including free:

Turn on code execution

Go to Settings → Capabilities and make sure code execution is turned on.

Add the skill

Go to Customize → Skills. Switch on any of Anthropic’s example skills, or upload your own skill folder as a ZIP file.

Some plugins are also listed in Anthropic’s plugin directory at claude.com/marketplace, which works with the app as well as Claude Code. Tool pages on this site say “Works in Claude Code and the Claude app” when that’s the case.