claude-builder

Claude Builder

A meta-development toolkit for creating Claude Code extensibility features. Build Skills, Subagents, Hooks, Commands, and Plugins faster with intelligent generators and proven templates.

Overview

Claude Builder is a comprehensive plugin that helps you create and manage Claude Code extensibility features. It uses a hybrid approach:

• Proactive Skills: Claude automatically helps when you're working on extensibility features
• Quick Commands: Explicit shortcuts when you want to create something immediately
• Validation Agents: Specialized subagents that check your configurations
• Template Library: Proven patterns for common use cases

Features

Core Generator Skills

1. skill-generator - Create new Skills with intelligent defaults

   • Auto-detects purpose from context
   • Generates proper YAML frontmatter
   • Creates supporting file structure
   • Suggests tool restrictions

2. plugin-scaffolder - Scaffold complete plugin structures

   • Creates full directory layout
   • Generates plugin.json manifest
   • Sets up all component directories
   • Initializes documentation

3. subagent-generator - Generate custom subagents

   • Creates properly formatted .md files
   • Suggests appropriate tool restrictions
   • Recommends model selection
   • Places in correct location

4. hook-generator - Create and configure hooks

   • Provides common hook templates
   • Updates settings.json safely
   • Validates hook configurations

5. extensibility-advisor - Choose the right approach

   • Helps decide between Skills, Commands, Subagents, and Hooks
   • Analyzes use cases and suggests best practices
   • Explains trade-offs

Quick Commands

Invoke these directly when you want immediate action:

• /new-skill [name] - Create a new Skill
• /new-plugin [name] - Scaffold a new plugin
• /new-agent [name] - Generate a new subagent
• /new-hook [event] - Create a new hook

Validation Subagents

• yaml-validator - Validates YAML frontmatter in Skills and agents
• structure-checker - Validates plugin directory structure

Template Library

Pre-built templates for common patterns:

Skills:

• code-reviewer
• test-runner
• doc-generator

Agents:

• debugger
• refactorer
• security-auditor

Hooks:

• auto-formatter
• pre-commit
• notification examples

Plugins:

• minimal-plugin
• full-featured-plugin

Installation

/plugin marketplace add squirrelsoft-dev/squirrelsoft-marketplace
/plugin install claude-builder@squirrelsoft-dev

From Local Directory

# Create a dev marketplace
mkdir -p ~/.claude/marketplaces/dev/.claude-plugin
echo '{"name": "dev", "description": "Development marketplace"}' > ~/.claude/marketplaces/dev/.claude-plugin/marketplace.json

# Link claude-builder plugin
ln -s /path/to/claude-builder ~/.claude/marketplaces/dev/claude-builder

# Add marketplace and install
/plugin marketplace add ~/.claude/marketplaces/dev
/plugin install claude-builder@dev

For Team Use

Add to your project's .claude/settings.json:

{
  "plugins": {
    "marketplaces": [
      {
        "path": "/path/to/marketplace"
      }
    ],
    "installed": [
      {
        "name": "claude-builder",
        "marketplace": "dev"
      }
    ]
  }
}

Usage

Proactive Mode (Skills Auto-Activate)

Just start discussing what you want to create:

You: I need a skill that helps me review security issues in code
Claude: [skill-generator activates and helps you create it]

Explicit Mode (Commands)

Use slash commands for immediate action:

You: /new-skill security-reviewer
Claude: [Creates a new security-reviewer skill with intelligent defaults]

Getting Advice

When unsure which approach to use:

You: I want to automatically format code after edits. Should I use a skill or a hook?
Claude: [extensibility-advisor explains that hooks are better for deterministic automation]

Examples

Creating a New Skill

You: I want to create a skill that helps me write API documentation
Claude: I'll help you create an API documentation skill. Let me generate it with intelligent defaults.

[skill-generator creates:]
- skills/api-doc-generator/SKILL.md
- Proper YAML frontmatter
- System prompt for API documentation
- Tool restrictions (Read, Grep, Glob for analyzing code)

Scaffolding a Plugin

You: /new-plugin team-productivity
Claude: Creating a new plugin structure...

[plugin-scaffolder creates:]
- team-productivity/
  - .claude-plugin/plugin.json
  - skills/
  - commands/
  - agents/
  - README.md

Creating a Subagent

You: I need a specialized agent for database query optimization
Claude: I'll create a database optimization subagent with appropriate tools.

[subagent-generator creates:]
- agents/db-optimizer.md
- Tool access: Read, Grep, Bash (for analyzing queries)
- Model: Sonnet (good balance for analysis)

Best Practices