skill-bootstrap

Skill Bootstrap

Purpose

Generate new skills rapidly from natural language descriptions. This skill prioritizes speed and compliance with the official Claude Agent Skills specification over bulletproofing.

For critical discipline-enforcing skills, use skill-hardening after bootstrapping.

When to Use

• Creating utility skills quickly
• Bootstrapping API wrappers or reference guides
• Generating skill scaffolding from descriptions
• Rapid prototyping of new capabilities
• Team-specific or project-specific tools

When NOT to use:

• Discipline-enforcing skills (use skill-hardening instead)
• Complex pattern skills requiring rigorous testing
• Skills that agents must follow under pressure

Quick Start

User: "Create a skill for validating JSON schemas"

You: [Use this skill to generate SKILL.md]

Official Skill Format

File Structure

.claude/skills/my-skill/
├── SKILL.md              # Required, uppercase
├── examples/             # Optional
│   └── usage.md
├── templates/            # Optional
│   └── template.yaml
└── scripts/              # Optional
    └── helper.py

SKILL.md Frontmatter

---
name: skill-name-lowercase-hyphenated
description: What the skill does, when to use it, trigger keywords. Max 1024 characters.
allowed-tools: Read, Grep, Glob  # Optional: restrict tool usage
---

Required fields:

• name: Lowercase with hyphens
• description: 200-1024 characters, include what/when/triggers

Optional fields:

• allowed-tools: Comma-separated tool restrictions

Do NOT include:

• version, category, activation_criteria, triggers (as array)

Description Best Practices

Critical: The description determines when Claude activates the skill.

Good description:

description: Validate JSON documents against JSON Schema specifications. Use when working with JSON validation, API request/response validation, or data integrity checks. Supports draft-07, draft-2019-09 schemas. Triggers on "JSON schema", "validate JSON", "schema validation".

Bad description:

description: Helps with Excel files  # Too vague

Bootstrap Process

Step 1: Parse Request

Extract:

• Name: lowercase-hyphenated
• Purpose: core functionality
• Triggers: keywords and use cases
• Scope: included/excluded

Step 2: Generate SKILL.md

Structure:

---
name: extracted-name
description: [Comprehensive description]
---

# Skill Name

## Purpose
Brief explanation

## When to Use
- Use case 1
- Use case 2

## Core Instructions
Step-by-step guidance

### Patterns and Examples
Code examples

## Dependencies (Optional)
Required tools/libraries

## Version
v1.0.0

Step 3: Evaluate Supporting Files

Create only if they add significant value:

• examples/ → for detailed usage patterns
• templates/ → for reusable structures
• scripts/ → for helper utilities

Use progressive disclosure:

For examples, see [examples/usage.md](examples/usage.md)

Step 4: Validate

Check:

• ✓ SKILL.md exists (uppercase)
• ✓ Frontmatter has name and description
• ✓ Description is 200-1024 characters
• ✓ No invalid frontmatter fields
• ✓ Supporting files referenced correctly

Tool Restrictions (allowed-tools)

Use when you want to restrict Claude's tools:

---
name: safe-file-reader
description: Read files without making changes
allowed-tools: Read, Grep, Glob
---

When to use:

• Read-only skills
• Safety-critical workflows
• Limited-scope operations

After Bootstrapping

For Utility Skills

Deploy and use. Monitor for issues.

For Discipline-Enforcing Skills

Required: Use skill-hardening to bulletproof the skill with TDD.

⚠️ This skill enforces discipline. Run skill-hardening to test it:
- Create pressure scenarios
- Verify agents comply under stress
- Close loopholes

Example: Simple Skill

Request: "Create a skill for validating JSON schemas"

Generated SKILL.md:

---
name: json-schema-validator
description: Validate JSON documents against JSON Schema specifications. Use when working with JSON validation, API request/response validation, configuration file validation, or data integrity checks. Supports draft-07, draft-2019-09, and draft-2020-12 schemas. Triggers on "JSON schema", "validate JSON", "schema validation", "JSON structure check".
---

# JSON Schema Validator

## Purpose
Validate JSON documents against JSON Schema specifications.

## When to Use
- Validating API payloads
- Checking configuration files
- Data integrity verification

## Core Instructions

1. **Identify Schema**: Locate the JSON Schema
2. **Load JSON**: Read the document to validate
3. **Validate**: Compare against schema rules
4. **Report**: List validation errors with paths

### Basic Validation Pattern

```python
import jsonschema
import json

def validate_json(data, schema):
    try:
        jsonschema.validate(instance=data, schema=schema)
        return True, "Valid"
    except jsonschema.exceptions.ValidationError as e:
        return False, str(e)

Dependencies

• Python 3.7+
• jsonschema library

Version

v1.0.0

## Example: Multi-File Skill

**Request:** "Create a skill for API testing with examples"

**Generated structure:**

.claude/skills/api-testing/ ├── SKILL.md ├── examples/ │ └── rest-api-example.md └── templates/ └── test-template.yaml

## Best Practices

### Keep It Minimal
- Don't create files just because you can
- Each supporting file should add value
- Examples should teach, not overwhelm

### Description Writing
- Start with action verbs: "Analyze", "Generate", "Transform"
- Include specific file types: ".xlsx", ".json", ".py"
- List concrete use cases
- End with explicit triggers

### Progressive Disclosure
Supporting files load on-demand. Reference them:
```markdown
See [examples/usage.md](examples/usage.md) for detailed examples.

Integration with Other Skills

Version

v1.0.0 (2025-01-28) - Bootstrap-focused refactor of skill-creator