# Sub-Agent Creator Automates creation of Claude Code sub-agents following Anthropic's official patterns, with proper frontmatter, tool configuration, and system prompts. ## Overview This skill guides users through creating production-ready sub-agents for Claude Code. It handles: - YAML frontmatter generation with required fields (`name`, `description`) - Tool permission configuration (security-focused minimal access) - Model selection (inherit, sonnet, opus, haiku) - System prompt structuring with role, approach, and constraints - Validation and testing guidance ## When to Use Use this skill when you need to: - Create specialized sub-agents for specific tasks (code review, debugging, data analysis) - Set up proactive agents that auto-trigger on task patterns - Configure secure tool permissions for agents - Build team-shared project-level agents (`.claude/agents/`) - Create personal user-level agents (`~/.claude/agents/`) ## Trigger Phrases - "create a sub-agent for [purpose]" - "generate a new sub-agent" - "set up a sub-agent to handle [task]" - "build a specialized agent for [domain]" - "help me create a sub-agent" - "make a proactive agent that [behavior]" ## Features ### Interactive Workflow Guides you through 5 phases: 1. **Information Gathering** - Purpose, name, description, location 2. **Technical Configuration** - Model, tools, system prompt components 3. **File Generation** - Create properly formatted sub-agent file 4. **Validation & Testing** - Verify configuration and provide test instructions 5. **Next Steps** - Guidance on refinement and best practices ### Security-First Tool Configuration - Defaults to minimal tool access - Warns about overly broad permissions - Recommends read-only tools for analysis agents - Requires explicit confirmation for "all tools" access ### Official Pattern Compliance - Follows Anthropic's sub-agent specification exactly - Proper YAML frontmatter with required fields - Correct storage locations (project vs. user level) - Proactive description patterns for auto-delegation ### Reference Materials Includes examples of production-ready sub-agents: - **code-reviewer** - Code quality, security, maintainability analysis - **debugger** - Root cause analysis and error resolution - **data-scientist** - SQL queries, statistical analysis, data visualization ## Prerequisites None - this skill works in any project or environment. Sub-agents are created as standalone markdown files. ## Installation This skill is available in the **claudex** marketplace. ### Local Installation (for development) ```bash # Copy to local skills directory cp -r sub-agent-creator ~/.claude/skills/ # Verify installation ls ~/.claude/skills/sub-agent-creator/SKILL.md ``` ### Marketplace Installation ```json // .claude/settings.json { "extraKnownMarketplaces": { "claudex": { "source": { "source": "github", "repo": "cskiro/claudex" } } }, "enabledPlugins": [ "sub-agent-creator@claudex" ] } ``` ## Usage Examples ### Example 1: Create a Code Reviewer **User:** "Create a sub-agent for code review" **Skill guides you through:** 1. Name suggestion: `code-reviewer` 2. Description: "Use PROACTIVELY to review code quality after significant changes" 3. Location: Project-level (`.claude/agents/`) for team sharing 4. Model: `inherit` (consistent with main session) 5. Tools: `Read, Grep, Glob, Bash` (read + search + execution) 6. System prompt: Focus on security, maintainability, best practices **Result:** `.claude/agents/code-reviewer.md` ready to use --- ### Example 2: Create a Data Analysis Agent **User:** "Set up a sub-agent to handle SQL queries" **Skill guides you through:** 1. Name: `data-scientist` 2. Description: "Use PROACTIVELY when data analysis or SQL queries are requested" 3. Location: User-level (`~/.claude/agents/`) for personal use across projects 4. Model: `sonnet` (balanced performance for data tasks) 5. Tools: `Read, Write, Bash, Grep, Glob` (data access + output generation) 6. System prompt: SQL expertise, statistical analysis, visualization recommendations **Result:** `~/.claude/agents/data-scientist.md` ready to use --- ### Example 3: Create a Debugging Specialist **User:** "Build a specialized agent for debugging test failures" **Skill guides you through:** 1. Name: `debugger` 2. Description: "Use PROACTIVELY when tests fail or errors occur" 3. Location: Project-level for team consistency 4. Model: `inherit` 5. Tools: `Read, Edit, Bash, Grep, Glob` (investigate + fix) 6. System prompt: Root cause analysis, hypothesis testing, minimal fixes **Result:** `.claude/agents/debugger.md` ready to use ## File Structure ``` sub-agent-creator/ ├── SKILL.md # Main skill manifest ├── README.md # This file ├── CHANGELOG.md # Version history ├── data/ │ ├── models.yaml # Available model options with guidance │ └── tools.yaml # Available tools with security notes ├── templates/ │ └── agent-template.md # System prompt structure template └── examples/ ├── code-reviewer.md # Example: Code review sub-agent ├── debugger.md # Example: Debugging sub-agent └── data-scientist.md # Example: Data analysis sub-agent ``` ## Configuration No configuration required - skill works out of the box. ## Best Practices 1. **Start with Minimal Tools** - Grant only necessary capabilities, expand as needed 2. **Use "PROACTIVELY" in Descriptions** - Enables automatic delegation 3. **Be Specific in System Prompts** - Include concrete examples and edge cases 4. **Test Before Deploy** - Verify agent loads and behaves correctly 5. **Iterate Based on Usage** - Refine after observing real-world behavior 6. **Document for Teams** - Project-level agents need clear usage guidance ## Validation The skill performs these validation checks: - ✅ YAML frontmatter is valid - ✅ Required fields present (`name`, `description`) - ✅ Tools list is valid (if specified) - ✅ Model value is valid (if specified) - ✅ No security issues (exposed secrets, overly broad permissions) - ✅ Description is specific enough for auto-delegation ## Troubleshooting ### Agent doesn't load ```bash # Check YAML syntax cat ~/.claude/agents/agent-name.md | head -10 # Verify frontmatter # Should show: --- name: agent-name description: ... --- ``` ### Agent has incorrect tools Edit the agent file and update the `tools:` field: ```yaml --- name: my-agent description: ... tools: Read, Grep, Glob # Add/remove tools here --- ``` ### Agent triggers too aggressively Refine the `description` field to be more specific: ```yaml # Too broad description: Use for code analysis # Better description: Use PROACTIVELY to analyze code quality when reviewing pull requests ``` ## Official Resources - **Anthropic Sub-Agent Docs:** https://docs.claude.com/en/docs/claude-code/sub-agents - **Claude Code Documentation:** https://docs.claude.com - **Claudex Marketplace:** https://github.com/cskiro/claudex ## Contributing Found a bug or have a feature request? Open an issue in the [claudex repository](https://github.com/cskiro/claudex/issues). ## License MIT License - see [LICENSE](https://github.com/cskiro/claudex/blob/main/LICENSE) for details. ## Version **Current Version:** 0.1.0 See [CHANGELOG.md](./CHANGELOG.md) for version history and updates. --- **Maintained by:** Connor **Status:** Proof of Concept **Last Updated:** 2025-11-02