Build skills, subagents, hooks, slash commands, and plugins for Claude Code — fast, consistently, and with best practices baked in.

Creating high-quality Claude Code customizations involves repetitive scaffolding and convention wrangling. Claude Code Builder gives you guided commands that generate the right files, structure, and docs — so you can focus on logic, not boilerplate.

For local development, contributors open a PR against this repo.
When the PR is merged into main, the marketplace manifest already points to this repo, so the plugin is live immediately (no extra publish step). Reviews and approvals are handled by the maintainer.

Summary

1. Fork + branch
2. Implement changes
3. Open PR → review
4. Merge to main → live in marketplace

1) Register the marketplace in Claude Code:

/plugin marketplace add alexanderop/claude-code-builder

2) Install the plugin from this marketplace:

/plugin install claude-code-builder@claude-code-builder

Check that commands appear:

/help
# Should see:
# /create-skill            - Create an auto-invoked Skill with best practices
# /create-agent            - Create a subagent with focused role/tools
# /create-command          - Generate a slash command (explicit invocation)
# /create-hook             - Configure event-driven hooks (pre/post tool use, etc.)
# /create-plugin           - Package a .claude/ setup into a plugin
# /create-md               - Generate CLAUDE.md files (project awareness)
# /create-output-style     - Create/activate custom Output Styles

Tip: If commands don’t appear, run /help again or restart Claude Code, then re-run the install command.

Each command opens a guided flow and prints the exact files/paths it creates.

# Skill (auto-invoked by Claude)
#/create-skill [skill-name] "[what it does and when to use it]"
/create-skill commit-helper "Generate clear commit messages; use when committing or reviewing staged changes."

# Subagent (focused role)
#/create-agent [name] "[when to invoke]" [--tools ...] [--model ...]
/create-agent reviewer "Expert code reviewer; use proactively after code changes" --tools "Read,Grep,Glob"

# Slash command (explicit invocation)
/create-command analyze-deps "Analyze dependencies for outdated packages"

# Hook (automate on events)
/create-hook PreToolUse "Edit|Write" "python3 .scripts/block_sensitive_edits.py"

# Package your setup as a plugin
/create-plugin

# Project awareness docs for Claude
/create-md very-thorough

# Output style for non-default workflows
/create-output-style "Teaching Assistant" --project --description "Explains step by step with examples"

# 1) Clone
git clone https://github.com/alexanderop/claude-code-builder.git
cd claude-code-builder

# 2) Start Claude Code
claude

# 3) Add a local marketplace and install
/plugin marketplace add .
/plugin install claude-code-builder@claude-code-builder-dev

You can iterate by editing files under commands/ and re-installing. For multi-plugin testing, create a parent test marketplace (e.g., dev-marketplace/) and place this repo inside it — /create-plugin prints exact paths and next steps.

claude-code-builder/
├── .claude-plugin/
│   ├── plugin.json              # Plugin manifest (name, version, repo, license)
│   └── marketplace.json         # Local marketplace for dev/testing
├── commands/                    # All slash-command sources (Markdown with frontmatter)
│   ├── create-skill.md
│   ├── create-agent.md
│   ├── create-command.md
│   ├── create-hook.md
│   ├── create-plugin.md
│   ├── create-md.md
│   └── create-output-style.md
├── README.md
├── LICENSE
└── .gitignore

• Convention over configuration — consistent file names, frontmatter, and paths.
• Safety rails — hooks and commands promote least-privilege tools and reviewability.
• Explainability — generated files include commented templates and examples.
• Distribution-ready — manifests and marketplace layout support team sharing.

• Claude Code installed (CLI + UI)
• Shell environment with common tooling (bash, jq, python3 for sample hooks)
• Git (for marketplace installs)

The plugin itself is language-agnostic; your generated Skills/agents can target any stack.

Where do files get created? User-level content goes under ~/.claude/...; project-level content under .claude/.... Commands print exact paths.

Can I block risky actions? Yes — use PreToolUse hooks that exit with code 2 to block operations (see /create-hook examples).

How do I share with my team? Use /create-plugin to package your .claude/ config and add it to a marketplace repo; teammates run the two install commands.

Issues and PRs are welcome 🎉

1. Check existing issues and discussions
2. Open a focused bug report or RFC
3. Submit a PR with clear description and before/after notes

• 1.0.0 – Initial release of all creation commands (2025-01-08)

See the repository for releases and change notes.

MIT — see LICENSE.

Alexander Opalic · https://github.com/alexanderop/claude-code-builder