Claude Code plugins and marketplaces: install or build

What a Claude Code plugin is, how to add a marketplace and install from it, how to check a plugin's cost before installing, and how to package your own skills, agents and hooks as a plugin.

By Behnia Zarei13 Oct 20263 min readClaude CodePlugins

Short answer: a plugin bundles skills, commands, agents, hooks, output styles and MCP servers into one install. Add a marketplace with claude plugin marketplace add owner/repo, then claude plugin install name@owner/repo, or use /plugin inside a session.

A plugin is a bundle of Claude Code pieces that arrive together: skills, commands, agents, hooks, output styles and MCP servers. Instead of copying six files into .claude/ by hand, you install one plugin, and you can turn it off again with one command.

How do I install a Claude Code plugin?

Plugins come from a marketplace, so you add one first:

claude plugin marketplace add owner/repo
claude plugin install my-plugin@owner/repo

A marketplace can be a GitHub repository, a URL or a local path. Nothing can be installed until one is added. The plugin@marketplace form picks the right one when two marketplaces offer the same name. Inside a session, /plugin does the same with a picker.

To switch one off without removing it:

claude plugin disable my-plugin
claude plugin enable my-plugin

What does a plugin cost before you install it?

A plugin's hooks run code on your machine, and its skills sit in every context. Before installing, look inside:

claude plugin details my-plugin@owner/repo

It prints the plugin's components and its projected token cost, and it works before you install. Adding a marketplace means trusting whoever controls it to ship code that runs on your machine, so this is the step worth not skipping.

How is a plugin laid out?

If you want to make one, the layout is strict:

my-plugin/
  .claude-plugin/plugin.json   the manifest, and the only file in this folder
  skills/<name>/SKILL.md       becomes /my-plugin:<name>
  commands/<name>.md
  agents/<name>.md
  output-styles/<name>.md
  hooks/hooks.json             plus the scripts it calls
  .mcp.json                    servers started when the plugin is enabled
  bin/                         added to the PATH the Bash tool sees
  README.md                    for people, not loaded by Claude

The mistake with no error message: putting skills/ or agents/ inside .claude-plugin/. The plugin installs and its components are never found. Only plugin.json goes in there.

What goes in the manifest?

{
  "name": "team-setup",
  "version": "1.0.0",
  "description": "Hooks and skills for working on this codebase.",
  "author": { "name": "Your Team" },
  "license": "MIT"
}

name is the only required field: lowercase, digits and hyphens. Setting version pins the plugin, so people only get updates when you bump it. Leave it out and every commit counts as a new version.

Inside a plugin, refer to bundled scripts through ${CLAUDE_PLUGIN_ROOT}, never an absolute path, because the install folder changes on every update.

What can a plugin not carry?

Some things in your setup do not travel in a plugin:

Permission rules and most settings. A plugin's own settings only support a couple of keys, so put the rules in the README for people to paste in
Your status line. It is a settings key. Ship the script in bin/ and give the one line to add
CLAUDE.md. A CLAUDE.md at the plugin root is not loaded. Turn it into a skill, which loads when it is relevant

And never package a real token: a plugin is made to be sent to someone, so a credential in one is a credential handed over.

Which marketplace names should you avoid?

Some marketplace names are reserved for Anthropic's own, such as claude-plugins-official and anthropic-plugins. A marketplace registered under a reserved name stops loading.

Where can you check this?

How do you turn your setup into a plugin?

Config Studio for Claude Code can export the plan you built (agents, skills, commands, output styles, hooks, MCP servers) as a ready plugin, a .zip you can try with claude --plugin-dir before you put it in a marketplace. It shows what was carried and what was left behind, with the reason for each, and refuses to package anything that looks like a credential. Its Plugins and marketplaces surface writes the install commands above for someone else's plugin.

The tool

Do it in your browser.

Claude Code

Config Studio for Claude Code

Every file Claude Code reads, explained: what each setting does, where it lives, which file wins, and an editor that writes it for you.

About the tool Open tool

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Every post

#How do I install a Claude Code plugin?

#What does a plugin cost before you install it?

#How is a plugin laid out?

#What goes in the manifest?

#What can a plugin not carry?

#Which marketplace names should you avoid?

#Where can you check this?

#How do you turn your setup into a plugin?