Skills and Plugins

Extend Claude Code with reusable instruction sets (skills) and installable plugin packages.

Claude Code supports two extension mechanisms: skills (reusable prompt-based instruction sets invoked as slash commands) and plugins (installable packages that can bundle skills, hooks, MCP servers, and agents).

Skills

A skill is a named instruction set that Claude can invoke via a slash command. When you type /skill-name, Claude loads the skill’s prompt and executes it with full access to its allowed tools.

Skills are useful for:

• Encoding team-specific workflows (e.g. /pr-review, /release-notes)
• Providing domain-specific context Claude doesn’t have by default
• Wrapping multi-step processes into a single invocable command

The /skills command

Type /skills in the Claude Code REPL to open the interactive skills browser. From there you can:

• Browse all available skills (bundled, project-local, and from plugins)
• Invoke a skill directly
• See its description and argument hint

Creating a skill

Create a Markdown file in .claude/skills/ in your project directory:

# .claude/skills/pr-review.md

Review the open pull request. Check for:
- Logic errors and edge cases
- Missing tests
- Documentation gaps
- Breaking changes

Report your findings as a structured list grouped by severity.

The filename (without .md) becomes the slash command name. The command above is invoked with /pr-review.

Skill frontmatter

Skills support YAML frontmatter for configuration:

---
description: Review the open pull request for quality issues
argumentHint: [PR number or branch name]
allowedTools:
  - Bash
  - Read
  - WebFetch
model: opus
---

Review the pull request...

Field	Description
description	Shown in /skills browser and autocomplete
argumentHint	Placeholder shown after the command name
allowedTools	Restrict which tools the skill can use
model	Override the model for this skill
whenToUse	Guidance for when Claude should suggest this skill
agent	Route the skill to a specific agent type
context	"inline" (default) or "fork" for isolated execution

Bundled skills

Claude Code ships with a set of built-in bundled skills compiled into the binary. These are always available and follow the same invocation pattern as project skills. Bundled skills may also be surfaced through built-in plugins.

Loading skills from files

Skills in .claude/skills/ in the current project directory are loaded automatically. Skills in a parent project’s .claude/skills/ directory are also available when working in a subdirectory.

You can also load a skill from an absolute path or URL by configuring it in project settings:

// .claude/settings.json
{
  "skills": [
    { "path": "/shared/team-skills/deploy.md" }
  ]
}

Plugins

A plugin is an installable package (typically from a Git repository) that can provide any combination of:

• Skills — slash commands
• Hooks — lifecycle event handlers
• MCP servers — custom tools
• Agents — custom agent definitions
• Output styles — custom rendering

Plugin IDs follow the format {name}@{marketplace}. Built-in plugins use the special {name}@builtin format.

The /plugins command

Use /plugins to browse, install, enable, and disable plugins. From the plugin manager you can:

• View installed plugins and their components
• Toggle individual plugins on or off
• Install a plugin from a Git URL or marketplace name

Built-in plugins

Built-in plugins ship with Claude Code and appear in the /plugins UI under a “Built-in” section. They can be toggled on or off — the preference is saved to your user settings.

A built-in plugin definition looks like this internally:

// BuiltinPluginDefinition shape (from src/types/plugin.ts)
{
  name: string                         // used in `{name}@builtin`
  description: string                  // shown in /plugins UI
  version?: string
  skills?: BundledSkillDefinition[]    // skills this plugin provides
  hooks?: HooksSettings                // lifecycle hooks
  mcpServers?: Record<string, McpServerConfig>
  defaultEnabled?: boolean             // default on/off (defaults to true)
  isAvailable?: () => boolean          // hide the plugin if unavailable
}

Skills contributed by built-in plugins appear alongside project skills in /skills and autocomplete.

Installing a plugin from a repository

# Install from a GitHub repository
/plugins install github:myorg/my-claude-plugin

# Install from a specific branch
/plugins install github:myorg/my-claude-plugin@main

Plugins are cloned into ~/.claude/plugins/ and their manifest is parsed to load components.

Plugin manifest

A plugin repository should include a manifest.json (or claude-plugin.json) at the root:

{
  "name": "my-plugin",
  "description": "Adds deployment and review skills",
  "version": "1.2.0",
  "skills": "./skills",
  "agents": "./agents",
  "hooks": "./hooks/config.json",
  "mcpServers": {
    "deploy-tools": {
      "type": "stdio",
      "command": "node",
      "args": ["./mcp/index.js"]
    }
  }
}

Plugin components

Skills from plugins

Skills in the plugin’s skills/ directory become slash commands, prefixed with nothing by default. Conflicts with existing skill names are resolved by the plugin manager.

Hooks from plugins

Plugins can define hooks for any lifecycle event. Hook scripts are executed alongside Claude Code’s own hook handlers.

// hooks/config.json
{
  "PostToolUse": [
    {
      "matcher": "Bash",
      "hooks": [{ "type": "command", "command": "node hooks/log-bash.js" }]
    }
  ]
}

MCP servers from plugins

MCP servers declared in the plugin manifest are started automatically when the plugin is enabled. They appear in /mcp and their tools are available to Claude.

Agents from plugins

Agent Markdown files in the plugin’s agents/ directory register as named agent types usable with the Agent tool’s subagent_type parameter.

Plugin error types

When a plugin fails to load, Claude Code surfaces a typed error. Common errors:

Error type	Cause
plugin-not-found	Plugin ID not found in the marketplace
git-auth-failed	SSH or HTTPS authentication error during clone
manifest-parse-error	Plugin manifest contains invalid JSON
mcp-config-invalid	An MCP server entry in the manifest is malformed
hook-load-failed	A hook script could not be loaded
dependency-unsatisfied	A required plugin dependency is not enabled

Comparison: skills vs plugins

	Skills	Plugins
Scope	Single slash command	Bundle of components
Location	.claude/skills/ or ~/.claude/skills/	Git repo, marketplace
Can include hooks	No (directly)	Yes
Can include MCP servers	No	Yes
User-toggleable	No	Yes (via /plugins)
Versioned	No	Yes (via Git SHA)