Skill Creator

This skill helps you create new Agent Skills that follow the official specification.

When to Use

User wants to create a new skill
User needs to scaffold a skill directory structure
User asks about skill format or structure
User wants to evaluate or validate an existing skill (e.g., "〜のスキルを評価して")

Steps to Create a New Skill

1. Gather Requirements

Ask the user for:

Skill name: Must be lowercase, use hyphens, 1-64 characters (e.g., pdf-processing, code-review)
Description: What the skill does and when to use it (1-1024 characters)
Optional: License, compatibility requirements, metadata

2. Confirm Installation Location

IMPORTANT: Before creating any files, confirm the installation location with the user.

Default Installation Path: .github/skills

The installation path varies by tool/environment. Determine a reasonable default based on:

Current working directory structure
Existing skills directories (e.g., ./skills/, ./.claude/skills/)
Project conventions

Then ask the user for confirmation:

スキル「{skill-name}」を以下の場所に作成します：
  {full-path}/{skill-name}/

この場所でよろしいですか？別の場所を指定することもできます。

Only proceed after user confirms the location.

3. Create Directory Structure

Create the skill directory at the confirmed location:

skill-name/
├── SKILL.md          # Required - main skill file
├── references/       # Optional - additional documentation
├── scripts/          # Optional - executable code
└── assets/           # Optional - static resources

4. Create SKILL.md

The SKILL.md file must contain:

YAML Frontmatter (required):

---
name: skill-name
description: A clear description of what this skill does and when to use it.
---

Markdown Body (recommended sections):
- Step-by-step instructions
- Examples of inputs and outputs
- Common edge cases

5. Validation Checklist

Before finishing, verify:

name field matches the directory name
name is lowercase with hyphens only, no consecutive hyphens
description clearly explains what the skill does AND when to use it
Main SKILL.md is under 500 lines
File references use relative paths from skill root

Name Constraints

The name field must:

Be 1-64 characters
Use only lowercase letters, numbers, and hyphens (a-z, 0-9, -)
Not start or end with -
Not contain consecutive hyphens (--)
Match the parent directory name exactly

Valid: pdf-processing, code-review, data-analysis Invalid: PDF-Processing, -pdf, pdf--processing, pdf-

Example SKILL.md

---
name: example-skill
description: Does X and Y. Use when the user mentions A, B, or C.
license: MIT
metadata:
  author: your-name
  version: "1.0"
---

# Example Skill

Instructions for the agent go here.

## Usage

1. First step
2. Second step

## Examples

Input: ...
Output: ...

Optional Directories

references/

Additional documentation loaded on demand. Keep files focused and small.

scripts/

Executable code (Python, Bash, JavaScript). Should be self-contained with clear error messages.

assets/

Static resources: templates, images, data files, schemas.

Evaluating an Existing Skill

When the user asks to evaluate a skill (e.g., "〜のスキルを評価して"), follow these steps:

1. Read the Specification

First, read skills-spec.md to understand the complete format requirements.

2. Read the Target Skill

Read the target skill's SKILL.md file and any related files.

3. Check Against Specification

Evaluate the skill against these criteria:

Required Checks:

SKILL.md exists in the skill directory
YAML frontmatter is present and valid
name field exists and follows naming rules:
- 1-64 characters
- Lowercase letters, numbers, hyphens only
- No leading/trailing hyphens
- No consecutive hyphens (--)
- Matches parent directory name
description field exists (1-1024 characters)
Description explains both WHAT the skill does AND WHEN to use it

Recommended Checks:

SKILL.md is under 500 lines
Body contains step-by-step instructions
Examples are provided
File references use relative paths
Reference files are focused and not too large

Optional Field Checks (if present):

license field is concise
compatibility field is under 500 characters
metadata has string keys and string values
allowed-tools is space-delimited

4. Report Findings

Present the evaluation results to the user:

List all issues found (errors and warnings)
Provide specific suggestions for each issue
Show example corrections where applicable

5. Wait for User Permission

IMPORTANT: Do NOT make any modifications automatically. Always:

Present the evaluation report
Ask the user if they want to apply the suggested fixes
Only proceed with modifications after explicit user approval

Example response format:

## 評価結果

### エラー (必須修正)
1. `name` フィールドが...

### 警告 (推奨修正)
1. `description` が...

### 修正案
[具体的な修正内容]

これらの修正を適用しますか？

Reference

For the complete specification, see skills-spec.md.

cp-skill-creator