Agent skill
claude-skill-builder
Interactive skill creator for Claude Code and Agent Skills ecosystem. Build SKILL.md files with proper frontmatter, triggers, and structure. Triggers on creating skills, building skills, skill templates, skill frontmatter, allowed-tools, npx add-skill, agent skills.
Install this agent skill to your Project
npx add-skill https://github.com/raintree-technology/claude-starter/tree/main/.claude/skills/anthropic/claude-skill-builder
Metadata
Additional technical details for this skill
- author
- raintree
- version
- 1.0
SKILL.md
Claude Code Skill Builder
Create well-structured skills compatible with Claude Code and the Agent Skills specification (used by npx add-skill).
When to Use
- User wants to create a new skill
- User needs help with skill structure or frontmatter
- User asks about trigger keywords or descriptions
- User wants to publish skills for
npx add-skill
Skill Structure
Minimal Skill (Single File)
skill-name/
└── SKILL.md
Full Skill (With References)
skill-name/
├── SKILL.md # Main skill file (required)
├── references/ # Additional documentation
│ └── api-guide.md
├── scripts/ # Helper scripts
│ └── helper.py
└── assets/ # Templates, examples
└── template.txt
SKILL.md Template
---
name: my-skill-name
description: Clear description of what this skill does. Include trigger keywords like keyword1, keyword2, keyword3 so the agent knows when to activate this skill.
allowed-tools: Read, Write, Edit, Grep, Glob, Bash
model: sonnet
license: MIT
metadata:
author: your-name
version: "1.0"
---
# Skill Title
## Purpose
Brief explanation of what this skill provides.
## When to Use
- Scenario 1 (include keywords)
- Scenario 2 (include keywords)
- Scenario 3 (include keywords)
## Process
### 1. Understand the Request
How to analyze what the user needs.
### 2. Gather Context
What information to collect.
### 3. Provide Solution
Step-by-step approach.
## Examples
### Example 1: Basic Usage
**Request:** "Help me with X"
**Response:** [How skill handles it]
## Best Practices
- Practice 1
- Practice 2
## Common Pitfalls
- Avoid X, do Y instead
Frontmatter Reference
Required Fields
| Field | Description | Example |
|---|---|---|
name |
Lowercase with hyphens, max 64 chars | nextjs-expert |
description |
What + When + Keywords, max 1024 chars | See below |
Optional Fields
| Field | Description | Values |
|---|---|---|
allowed-tools |
Tools skill can use | Read, Write, Edit, Grep, Glob, Bash |
model |
AI model preference | haiku, sonnet, opus |
license |
License type | MIT, Apache-2.0 |
metadata.author |
Skill author | Your name |
metadata.version |
Semantic version | "1.0" |
Writing Effective Descriptions
Good description (includes what, when, keywords):
description: Expert in Next.js App Router, server components, and React Server Components. Use when user mentions Next.js, RSC, App Router, server actions, or React server-side patterns.
Bad description (too vague):
description: Helps with Next.js
Skill Types
1. Framework/API Expert
Purpose: Deep knowledge of specific technology
Triggers: Framework name, features, patterns
Tools: Read, Grep, Glob
name: fastapi-expert
description: FastAPI web framework expert covering routing, dependencies, Pydantic models, async endpoints, and OpenAPI generation. Triggers on FastAPI, Python API, Pydantic, async web.
2. Code Generator
Purpose: Create boilerplate or scaffolding
Triggers: "generate", "create", "scaffold"
Tools: Write, Read, Grep, Glob
name: component-generator
description: Generate React components with TypeScript, tests, and stories. Triggers on generate component, create component, scaffold component.
3. Code Analyzer
Purpose: Review and analyze code
Triggers: "review", "analyze", "audit"
Tools: Read, Grep, Glob
name: security-auditor
description: Security code review for common vulnerabilities including XSS, SQL injection, and OWASP Top 10. Triggers on security review, audit code, find vulnerabilities.
4. Workflow Automator
Purpose: Automate development tasks
Triggers: Task-specific keywords
Tools: Read, Write, Edit, Bash
name: release-helper
description: Automate release workflows including changelog generation, version bumping, and git tagging. Triggers on release, changelog, version bump, tag release.
5. Data Processor
Purpose: Transform or analyze data
Triggers: Format names, transformation keywords
Tools: Read, Write, Edit, Grep
name: csv-processor
description: Parse, transform, and analyze CSV files. Convert between CSV, JSON, and other formats. Triggers on CSV, parse CSV, convert CSV.
Publishing for npx add-skill
Skills following this format work with npx add-skill from any Git repository.
Repository Structure
your-repo/
├── skills/
│ ├── skill-one/
│ │ └── SKILL.md
│ └── skill-two/
│ └── SKILL.md
└── README.md
Installation Commands
# Users install from your repo
npx add-skill your-username/your-repo
# List available skills
npx add-skill your-username/your-repo --list
# Install specific skill
npx add-skill your-username/your-repo --skill my-skill
# Direct link to skill
npx add-skill https://github.com/user/repo/tree/main/skills/my-skill
Installation Locations
| Scope | Path | Use Case |
|---|---|---|
| Personal | ~/.claude/skills/ |
Your own tools |
| Project | .claude/skills/ |
Team-shared skills |
Interactive Skill Creation
When helping users create skills, gather:
- Skill name - lowercase-with-hyphens
- What it does - 1-2 sentence description
- When to activate - trigger keywords
- Tools needed - Read, Write, Edit, Grep, Glob, Bash
- Scope - personal or project
Then generate the SKILL.md with proper structure.
Validation Checklist
Before publishing:
- Name is lowercase with hyphens only
- Description includes trigger keywords
- Description explains both WHAT and WHEN
- SKILL.md filename is uppercase
- YAML frontmatter is valid (no tabs)
- Only necessary tools are requested
- Examples are included
- Under 500 lines (move details to references/)
Troubleshooting
Skill Not Activating
- Check description has specific keywords
- Verify file is named
SKILL.md(uppercase) - Confirm path:
~/.claude/skills/name/SKILL.mdor.claude/skills/name/SKILL.md - Validate YAML syntax (no tabs, proper indentation)
- Restart Claude Code
Skill Conflicts
Multiple skills with similar triggers:
- Make descriptions more specific
- Use distinct keywords
- Consider combining into one skill
Resources
- Agent Skills Spec: https://agentskills.io
- Claude Code Docs: https://docs.anthropic.com/en/docs/claude-code
- npx add-skill: https://github.com/vercel-labs/add-skill
Recommended Agent Skills
Expand your agent's capabilities with these related and highly-rated skills.
claude-mcp-expert
Model Context Protocol (MCP) expert for Claude Code. Install, configure, and troubleshoot MCP servers. Covers HTTP, SSE, and stdio transports, authentication, popular integrations (Sentry, GitHub, Jira, Notion, databases). Triggers on MCP, Model Context Protocol, MCP server, installing MCP, connecting tools, webhooks, remote server.
move-prover
Move Prover formal verification expert for Aptos smart contracts. Write specifications (MSL), preconditions (requires), postconditions (ensures), invariants, abort conditions (aborts_if), quantifiers, schemas, and pragmas. Debug verification failures. Triggers on Move Prover, formal verification, spec, invariant, ensures, requires, aborts_if, precondition, postcondition.
helius
Helius Solana RPC and API expert. High-performance infrastructure for Solana including RPC nodes, DAS API for NFTs/tokens, LaserStream real-time streaming, webhooks, Priority Fee API, Enhanced Transactions, and ZK Compression. Triggers on Helius, Solana RPC, DAS API, Digital Asset Standard, NFT metadata, Solana webhooks, priority fees, LaserStream, ZK compression.
toon-formatter
Token-Oriented Object Notation (TOON) format expert for 30-60% token savings on structured data. Auto-applies to arrays with 5+ items, tables, logs, API responses, database results. Supports tabular, inline, and expanded formats with comma/tab/pipe delimiters. Triggers on large JSON, data optimization, token reduction, structured data, arrays, tables, logs, metrics, TOON.
aptos
Aptos blockchain and Move language expert. Covers Move programming (abilities, generics, resources), Aptos framework modules, smart contract development, token standards (Coin, Fungible Asset, Digital Asset), object model, gas optimization, and dApp integration. Triggers on Aptos, Move language, Move smart contract, Aptos blockchain, abilities, generics, resources, fungible asset, digital asset.
aptos-move-testing
Expert on testing Move smart contracts including unit tests, integration tests, Move Prover formal verification, debugging strategies, test coverage, and CI/CD integration for Aptos development.
Didn't find tool you were looking for?