claude-howto/CATALOG.md

Claude Code Feature Catalog

Quick reference guide to all Claude Code features: commands, agents, skills, plugins, and hooks.

Navigation: Commands | Sub-Agents | Skills | Plugins | MCP Servers | Hooks | Token Legend

---

Token Estimation Legend

Each feature table includes Tokens and Scope columns to help you manage context budget and installation decisions.

Estimation Methodology

Factor	Description
Base Calculation	~1 token ≈ 4 characters of English text
Markdown Overhead	YAML frontmatter, headers, formatting add ~10-15%
Reference Files	Skills with multiple files (scripts, templates) include all loadable content
Dynamic Content	MCP tools and hooks show config overhead only; actual tool calls add more

Token Ranges by Feature Type

Feature Type	Typical Range	What's Included
Commands	300-800	Markdown file content + YAML metadata
Sub-Agents	600-1000	System prompt + tool definitions
Skills	1000-3000	SKILL.md + referenced files (scripts, templates)
Plugins	4000-6000	All bundled components combined
MCP Servers	50-200	JSON config only (tool schemas loaded on-demand)
Hooks	20-50	Hook config entry (scripts run externally)
Memory	200-2000	Varies by content length (loaded every session)

Scope Recommendations

Scope	Location	Best For
User	~/.claude/	Personal preferences, individual workflows
Project	.claude/ or ./	Team standards, shared configurations
Directory	./path/to/dir/	Module-specific rules (memory only)
Built-in	N/A	Pre-installed, no configuration needed

Context Budget Tips

• Claude's context window: ~200K tokens (model-dependent)
• Keep memory files concise: Every token in CLAUDE.md is loaded every session
• Skills load on-demand: Only when auto-invoked, not at startup
• Plugins are heavy: Consider installing only what you actively use
• Use /context: Check current usage anytime

---

Slash Commands

Commands are user-invoked shortcuts that execute specific actions.

Built-in Commands

Command	Description	When to Use
/help	Show help information	Get started, learn commands
/clear	Clear conversation history	Start fresh, reduce context
/model	Switch AI model	Change performance/cost
/config	View/edit configuration	Customize behavior
/status	Show session status	Check current state
/agents	List available agents	See delegation options
/skills	List available skills	See auto-invoke capabilities
/hooks	List configured hooks	Debug automation
/mcp	List MCP servers	Check external integrations
/memory	View loaded memory files	Debug context loading
/plugin	Manage plugins	Install/remove extensions
/plan	Enter planning mode	Complex implementations
/rewind	Rewind to checkpoint	Undo changes, explore alternatives
/checkpoint	Manage checkpoints	Save/restore states
/cost	Show token usage costs	Monitor spending
/context	Show context window usage	Manage conversation length
/export	Export conversation	Save for reference
/login	Authenticate with Anthropic	Access features
/logout	Sign out	Switch accounts
/sandbox	Toggle sandbox mode	Safe command execution
/vim	Toggle vim mode	Vim-style editing
/doctor	Run diagnostics	Troubleshoot issues
/release-notes	Show release notes	Check new features
/permissions	Manage permissions	Control access
/session	Manage sessions	Multi-session workflows
/rename	Rename current session	Organize sessions
/resume	Resume previous session	Continue work
/todo	View/manage todo list	Track tasks
/tasks	View background tasks	Monitor async operations

Custom Commands (Examples)

Command	Description	When to Use	Tokens	Scope	Installation
/optimize	Analyze code for optimization	Performance improvement	~500	Project	cp 01-slash-commands/optimize.md .claude/commands/
/pr	Prepare pull request	Before submitting PRs	~400	Project	cp 01-slash-commands/pr.md .claude/commands/
/generate-api-docs	Generate API documentation	Document APIs	~600	Project	cp 01-slash-commands/generate-api-docs.md .claude/commands/
/commit	Create git commit with context	Commit changes	~300	User	cp 01-slash-commands/commit.md .claude/commands/
/push-all	Stage, commit, and push	Quick deployment	~400	User	cp 01-slash-commands/push-all.md .claude/commands/
/doc-refactor	Restructure documentation	Improve docs	~500	Project	cp 01-slash-commands/doc-refactor.md .claude/commands/
/setup-ci-cd	Setup CI/CD pipeline	New projects	~800	Project	cp 01-slash-commands/setup-ci-cd.md .claude/commands/
/unit-test-expand	Expand test coverage	Improve testing	~600	Project	cp 01-slash-commands/unit-test-expand.md .claude/commands/

Tokens: Estimated context consumed when command is loaded. Scope: User = personal workflows (~/.claude/), Project = team-shared (.claude/)

Reference: 01-slash-commands/ | Official Docs

Quick Install (All Custom Commands):

cp 01-slash-commands/*.md .claude/commands/

---

Sub-Agents

Specialized AI assistants with isolated contexts for specific tasks.

Built-in Sub-Agents

Agent	Description	Tools	Model	When to Use
general-purpose	Multi-step tasks, research	All tools	Sonnet	Complex research, multi-file tasks
Explore	Codebase exploration	Read, Glob, Grep	Haiku	Quick searches, understanding code
Plan	Implementation planning	Read, Glob, Grep, Bash	Sonnet	Architecture design, planning
Bash	Command execution	Bash	Sonnet	Git operations, terminal tasks
code-reviewer	Code quality analysis	Read, Glob, Grep	Sonnet	PR reviews, quality checks
code-architect	Feature architecture design	Read, Glob, Grep, LS	Sonnet	New feature planning
code-explorer	Deep codebase analysis	Read, Glob, Grep, LS	Sonnet	Understanding existing features
clean-code-reviewer	Clean Code principles	Read, Grep, Glob, Bash	Sonnet	Maintainability review

Custom Sub-Agents (Examples)

Agent	Description	When to Use	Tokens	Scope	Installation
code-reviewer	Comprehensive code quality	Code review sessions	~800	Project	cp 04-subagents/code-reviewer.md .claude/agents/
test-engineer	Test strategy & coverage	Test planning	~700	Project	cp 04-subagents/test-engineer.md .claude/agents/
documentation-writer	Technical documentation	API docs, guides	~600	Project	cp 04-subagents/documentation-writer.md .claude/agents/
secure-reviewer	Security-focused review	Security audits	~900	Project	cp 04-subagents/secure-reviewer.md .claude/agents/
implementation-agent	Full feature implementation	Feature development	~1000	Project	cp 04-subagents/implementation-agent.md .claude/agents/
debugger	Root cause analysis	Bug investigation	~700	User	cp 04-subagents/debugger.md .claude/agents/
data-scientist	SQL queries, data analysis	Data tasks	~600	User	cp 04-subagents/data-scientist.md .claude/agents/

Tokens: Estimated context consumed when agent is invoked. Scope: User = personal (~/.claude/agents/), Project = team-shared (.claude/agents/)

Reference: 04-subagents/ | Official Docs

Quick Install (All Custom Agents):

cp 04-subagents/*.md .claude/agents/

---

Skills

Auto-invoked capabilities with instructions, scripts, and templates.

Example Skills

Skill	Description	When Auto-Invoked	Tokens	Scope	Installation
code-review	Comprehensive code review	"Review this code", "Check quality"	~2000	Project	cp -r 03-skills/code-review .claude/skills/
brand-voice	Brand consistency checker	Writing marketing copy	~1200	Project	cp -r 03-skills/brand-voice .claude/skills/
doc-generator	API documentation generator	"Generate docs", "Document API"	~1500	Project	cp -r 03-skills/doc-generator .claude/skills/
refactor	Systematic code refactoring (Martin Fowler)	"Refactor this", "Clean up code"	~3000	User	cp -r 03-skills/refactor ~/.claude/skills/

Tokens: Estimated context when skill + references loaded. Scope: User = personal (~/.claude/skills/), Project = team-shared (.claude/skills/)

Skill Structure

~/.claude/skills/skill-name/
├── SKILL.md          # Skill definition & instructions
├── scripts/          # Helper scripts
└── templates/        # Output templates

Reference: 03-skills/ | Official Docs

Quick Install (All Skills):

cp -r 03-skills/* ~/.claude/skills/

---

Plugins

Bundled collections of commands, agents, MCP servers, and hooks.

Example Plugins

Plugin	Description	Components	When to Use	Tokens	Scope	Installation
pr-review	PR review workflow	3 commands, 3 agents, GitHub MCP	Code reviews	~5000	Project	/plugin install pr-review
devops-automation	Deployment & monitoring	4 commands, 3 agents, K8s MCP	DevOps tasks	~6000	Project	/plugin install devops-automation
documentation	Doc generation suite	4 commands, 3 agents, templates	Documentation	~4000	Project	/plugin install documentation

Tokens: Total context when all plugin components loaded. Scope: Project = team-shared, User = personal workflows

Plugin Structure

.claude-plugin/
├── plugin.json       # Manifest file
├── commands/         # Slash commands
├── agents/           # Sub-agents
├── skills/           # Skills
├── mcp/              # MCP configurations
├── hooks/            # Hook scripts
└── scripts/          # Utility scripts

Reference: 07-plugins/ | Official Docs

Plugin Management Commands:

/plugin list              # List installed plugins
/plugin install <name>    # Install plugin
/plugin remove <name>     # Remove plugin
/plugin update <name>     # Update plugin

---

MCP Servers

Model Context Protocol servers for external tool and API access.

Common MCP Servers

Server	Description	When to Use	Tokens	Scope	Installation
GitHub	PR management, issues, code	GitHub workflows	~200	Project	cp 05-mcp/github-mcp.json .claude/mcp.json
Database	SQL queries, data access	Database operations	~150	Project	cp 05-mcp/database-mcp.json .claude/mcp.json
Filesystem	Advanced file operations	Complex file tasks	~100	User	cp 05-mcp/filesystem-mcp.json .claude/mcp.json
Slack	Team communication	Notifications, updates	~150	Project	Configure in settings
Google Docs	Document access	Doc editing, review	~200	Project	Configure in settings
Asana	Project management	Task tracking	~150	Project	Configure in settings
Stripe	Payment data	Financial analysis	~200	Project	Configure in settings
Memory	Persistent memory	Cross-session recall	~100	User	Configure in settings
Context7	Library documentation	Up-to-date docs lookup	~50	Built-in	Built-in

Tokens: Config overhead (tool calls add more). Scope: Project = team (.claude/mcp.json), User = personal (~/.claude/mcp.json)

MCP Configuration Example

{
  "mcpServers": {
    "github": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-github"],
      "env": {
        "GITHUB_TOKEN": "${GITHUB_TOKEN}"
      }
    }
  }
}

Reference: 05-mcp/ | MCP Protocol Docs

Quick Install (GitHub MCP):

export GITHUB_TOKEN="your_token" && cp 05-mcp/github-mcp.json .claude/mcp.json

---

Hooks

Event-driven automation that executes shell commands on Claude Code events.

Hook Events

Event	Description	When Triggered	Use Cases
PreToolUse	Before tool execution	Before any tool runs	Validation, logging
PostToolUse	After tool completion	After any tool completes	Formatting, notifications
PermissionRequest	Permission dialog shown	Before sensitive actions	Custom approval flows
UserPromptSubmit	Before prompt processing	User sends message	Input validation
Notification	Notification sent	Claude sends notification	External alerts
Stop	Agent finishes responding	Response complete	Cleanup, reporting
SubagentStop	Subagent finishes	Subagent task complete	Chain actions
PreCompact	Before compact operation	Context compression	State preservation
SessionStart	Session begins/resumes	Session initialization	Setup tasks

Example Hooks

Hook	Description	Event	Tokens	Scope	Installation
validate-bash.py	Command validation	PreToolUse:Bash	~50	Project	cp 06-hooks/validate-bash.py .claude/hooks/
security-scan.py	Security scanning	PostToolUse:Write	~50	Project	cp 06-hooks/security-scan.py .claude/hooks/
format-code.sh	Auto-formatting	PostToolUse:Write	~30	User	cp 06-hooks/format-code.sh ~/.claude/hooks/
validate-prompt.py	Prompt validation	UserPromptSubmit	~50	Project	cp 06-hooks/validate-prompt.py .claude/hooks/
context-tracker.py	Token usage tracking	Stop	~40	User	cp 06-hooks/context-tracker.py ~/.claude/hooks/
pre-commit.sh	Pre-commit validation	PreToolUse:Bash	~30	Project	cp 06-hooks/pre-commit.sh .claude/hooks/
log-bash.sh	Command logging	PostToolUse:Bash	~20	User	cp 06-hooks/log-bash.sh ~/.claude/hooks/

Tokens: Config overhead only (scripts run externally). Scope: Project = team (.claude/settings.json), User = personal (~/.claude/settings.json)

Hook Configuration

{
  "hooks": {
    "PreToolUse": [
      {
        "matcher": "Bash",
        "command": "~/.claude/hooks/validate-bash.py"
      }
    ],
    "PostToolUse": [
      {
        "matcher": "Write",
        "command": "~/.claude/hooks/format-code.sh"
      }
    ]
  }
}

Reference: 06-hooks/ | Official Docs

Quick Install (All Hooks):

mkdir -p ~/.claude/hooks && cp 06-hooks/*.sh ~/.claude/hooks/ && chmod +x ~/.claude/hooks/*.sh

---

Memory Files

Persistent context loaded automatically across sessions.

Memory Types

Type	Location	Scope	Tokens	When to Use
Project Memory	./CLAUDE.md	Project (team)	~500-2000	Team standards, project rules
Directory Memory	./src/api/CLAUDE.md	Directory	~200-500	Module-specific rules
Personal Memory	~/.claude/CLAUDE.md	User (personal)	~300-1000	Personal preferences

Tokens: Varies by content length (auto-loaded every session). Keep memory files concise to preserve context for actual work.

Reference: 02-memory/ | Official Docs

Quick Install:

cp 02-memory/project-CLAUDE.md ./CLAUDE.md
cp 02-memory/personal-CLAUDE.md ~/.claude/CLAUDE.md

---

Quick Reference Matrix

Feature Selection Guide

Need	Recommended Feature	Why
Quick shortcut	Slash Command	Manual, immediate
Persistent context	Memory	Auto-loaded
Complex automation	Skill	Auto-invoked
Specialized task	Sub-Agent	Isolated context
External data	MCP Server	Real-time access
Event automation	Hook	Event-triggered
Complete solution	Plugin	All-in-one bundle

Installation Priority

Priority	Feature	Command
1. Essential	Memory	cp 02-memory/project-CLAUDE.md ./CLAUDE.md
2. Daily Use	Slash Commands	cp 01-slash-commands/*.md .claude/commands/
3. Quality	Sub-Agents	cp 04-subagents/*.md .claude/agents/
4. Automation	Hooks	cp 06-hooks/*.sh ~/.claude/hooks/ && chmod +x ~/.claude/hooks/*.sh
5. External	MCP	cp 05-mcp/github-mcp.json .claude/mcp.json
6. Advanced	Skills	cp -r 03-skills/* ~/.claude/skills/
7. Complete	Plugins	/plugin install pr-review

---

Complete One-Command Installation

Install all examples from this repository:

# Create directories
mkdir -p .claude/{commands,agents,skills} ~/.claude/{hooks,skills}

# Install all features
cp 01-slash-commands/*.md .claude/commands/ && \
cp 02-memory/project-CLAUDE.md ./CLAUDE.md && \
cp -r 03-skills/* ~/.claude/skills/ && \
cp 04-subagents/*.md .claude/agents/ && \
cp 06-hooks/*.sh ~/.claude/hooks/ && \
chmod +x ~/.claude/hooks/*.sh

---

Additional Resources

• Official Claude Code Documentation
• MCP Protocol Specification
• Learning Roadmap
• Main README

---

Last Updated: January 2026