Marketplace create-new-skills
Creates new Agent Skills for Claude Code following best practices and documentation. Use when the user wants to create a new skill, extend Claude's capabilities, or package domain expertise into a reusable skill.
git clone https://github.com/aiskillstore/marketplace
T=$(mktemp -d) && git clone --depth=1 https://github.com/aiskillstore/marketplace "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/egadams/create-new-skills" ~/.claude/skills/aiskillstore-marketplace-create-new-skills && rm -rf "$T"
skills/egadams/create-new-skills/SKILL.mdCreate New Skills
Instructions
This skill helps you create new Agent Skills for Claude Code. Before starting, read the comprehensive documentation files in the docs/ directory for complete context.
Prerequisites
Required Reading - Read these files in order before creating a skill:
- docs/claude_code_agent_skills.md - Complete guide to creating and managing skills
- docs/claude_code_agent_skills_overview.md - Architecture and how skills work
- docs/blog_equipping_agents_with_skills.md - Design principles and best practices
Understanding Skills
What is a Skill?
- A directory containing a
file with YAML frontmatterSKILL.md - Instructions that Claude loads on-demand when relevant
- Optional supporting files (scripts, documentation, templates)
- Like an onboarding guide for a new team member
Progressive Disclosure (3 Levels):
- Metadata (always loaded):
andname
in YAML frontmatterdescription - Instructions (loaded when triggered): Main body of SKILL.md
- Resources (loaded as needed): Additional files, scripts, templates
Key Principle: Only relevant content enters the context window at any time.
Skill Creation Workflow
Step 1: Define the Skill's Purpose
Ask the user these questions:
- What task or domain should this skill cover?
- When should Claude use this skill? (triggers)
- What expertise or workflows need to be captured?
- Does it need scripts, templates, or other resources?
Document the answers for reference.
Step 2: Create the Skill Directory Structure
Create skills in the project's
.claude/skills/ directory for team sharing:
mkdir -p .claude/skills/<skill-name>
Naming conventions:
- Use lowercase with hyphens (e.g.,
,pdf-processing
)data-analysis - Be descriptive but concise
- Avoid generic names
Note: Project skills (
.claude/skills/) are automatically shared with your team via git. For personal skills only you use, create in ~/.claude/skills/ instead.
Step 3: Design the SKILL.md Structure
Every skill must have:
--- name: Your Skill Name description: Brief description of what this Skill does and when to use it --- # Your Skill Name ## Instructions [Clear, step-by-step guidance for Claude] ## Examples [Concrete examples of using this Skill]
Frontmatter Requirements:
: Required, max 64 charactersname
: Required, max 1024 charactersdescription- Include BOTH what it does AND when to use it
- Mention key trigger words/phrases
- Be specific, not vague
Optional Frontmatter (Claude Code only):
: Restrict which tools Claude can use (e.g.,allowed-tools
)Read, Grep, Glob
Step 4: Write the Instructions Section
Structure the instructions as:
- Prerequisites - Required dependencies, tools, environment setup
- Workflow - Step-by-step process (numbered steps)
- Supporting Details - Additional context, script usage, error handling
Best Practices:
- Use clear, actionable language
- Number sequential steps
- Use bullet points for options/lists
- Include code blocks with bash commands
- Reference supporting files with relative links:
[reference.md](reference.md) - Keep focused on one capability
Example workflow format:
### Workflow 1. **First step description**: ```bash command to run
- Additional context
- Options or variations
-
Second step description:
- Detailed instructions
- What to look for
- Expected outcomes
-
Third step...
#### Step 5: Write the Examples Section Provide 2-4 concrete examples showing: - Different use cases - Various input formats - Step-by-step execution - Expected outcomes **Example format:** ```markdown ### Example 1: Descriptive Title User request:
User's exact request text
You would: 1. First action 2. Second action with command: ```bash actual command
- Next steps...
- Final result
#### Step 6: Add Supporting Files (Optional) If the skill needs additional context: 1. Create files alongside SKILL.md 2. Reference them from instructions: `[forms.md](forms.md)` 3. Use progressive disclosure - split by topic/scenario **Common supporting file types:** - Additional instructions (e.g., `advanced_usage.md`) - Reference documentation (e.g., `api_reference.md`) - Scripts in `scripts/` directory - Templates in `templates/` directory - Configuration examples **Script guidelines:** - Make executable: `chmod +x scripts/*.py` - Add PEP 723 inline dependencies for Python scripts - Include usage instructions in SKILL.md - Return clear output for Claude to parse #### Step 7: Test the Skill 1. Verify file structure: ```bash ls -la .claude/skills/<skill-name>/
-
Check YAML frontmatter is valid:
head -10 .claude/skills/<skill-name>/SKILL.md -
Test with relevant queries:
- Ask questions matching the skill's description
- Verify Claude loads and uses the skill
- Check that instructions are clear and actionable
-
Iterate based on testing:
- Refine description if skill doesn't trigger
- Clarify instructions if Claude struggles
- Add examples for common edge cases
Step 8: Commit to Version Control
Since project skills are automatically shared with your team, commit them to git:
git add .claude/skills/<skill-name> git commit -m "Add <skill-name> skill" git push
Note: Team members will get the skill automatically when they pull the latest changes.
Best Practices Summary
Description writing:
- ✅ "Transcribes audio/video files to text using Fireworks API. Use when user asks to transcribe, convert speech to text, or needs transcripts."
- ❌ "Helps with audio"
Instruction organization:
- Keep main instructions focused (under 5k tokens ideal)
- Split complex content into linked files
- Use progressive disclosure for optional/advanced content
Skill scope:
- One skill = one capability or workflow
- Don't combine unrelated tasks
- Make focused, composable skills
File references:
- Use relative paths:
not absolute paths[file.md](file.md) - Reference scripts with full path from skill root
- Make it clear when Claude should read vs execute files
Common Patterns from Existing Skills
Pattern 1: Transcription skill
- Prerequisites section with environment setup
- Clear numbered workflow
- Multiple examples showing different formats
- Supporting file for corrections/mappings
Pattern 2: Morning debrief skill
- Two-step process (transcribe, extend)
- Reference to detailed prompt in separate file
- File organization step
- Clear output structure specification
Pattern 3: Meta-skill (this one)
- Extensive prereading documentation
- Step-by-step creation workflow
- Multiple examples with variations
- Best practices and common patterns
Examples
Example 1: Creating a Simple Code Review Skill
User request:
Create a skill that reviews Python code for best practices
You would:
- Read the documentation files in docs/
- Ask clarifying questions:
- What specific best practices? (PEP 8, security, performance?)
- Should it check only or suggest fixes?
- Any specific frameworks or libraries?
- Create the skill directory:
mkdir -p .claude/skills/python-code-review - Write SKILL.md with:
--- name: Python Code Review description: Reviews Python code for PEP 8 compliance, security issues, and performance. Use when reviewing Python code, checking code quality, or analyzing Python files. allowed-tools: Read, Grep, Glob --- - Add Instructions section with:
- Prerequisites (none needed, uses built-in tools)
- Workflow:
- Read the Python file(s)
- Check PEP 8 compliance
- Identify security issues
- Suggest performance improvements
- Provide summary with specific line references
- Add 3 examples:
- Example 1: Single file review
- Example 2: Multi-file project review
- Example 3: Focused security review
- Test with sample Python files
Example 2: Creating a Data Analysis Skill with Scripts
User request:
Build a skill for analyzing CSV data with statistics and visualizations
You would:
- Read documentation files
- Define scope with user:
- What statistics? (mean, median, correlations?)
- What visualizations? (charts, plots?)
- Output format? (markdown report, images?)
- Create structure:
mkdir -p .claude/skills/csv-analysis/scripts mkdir -p .claude/skills/csv-analysis/templates - Write SKILL.md referencing:
- Statistical analysis scriptscripts/analyze.py
- Chart generation scriptscripts/visualize.py
- Output templatetemplates/report_template.md
- Create Python scripts with inline dependencies:
# /// script # requires-python = ">=3.10" # dependencies = ["pandas", "matplotlib", "seaborn"] # /// - Write clear instructions for:
- When to run which script
- How to interpret output
- How to customize analysis
- Add examples showing:
- Basic statistics
- Visualization generation
- Custom report creation
- Test with sample CSV files
Example 3: Creating a Multi-File Documentation Skill
User request:
Create a skill for writing technical documentation with our company's style guide
You would:
- Read documentation files
- Gather requirements:
- Get company style guide document
- What types of docs? (API, user guides, architecture?)
- Any templates or examples?
- Create comprehensive structure:
mkdir -p .claude/skills/tech-docs/{templates,examples,guidelines} - Organize content:
- Overview and workflowSKILL.md
- Company style rulesguidelines/style_guide.md
- API documentation specificsguidelines/api_docs.md
- User guide standardsguidelines/user_guides.md
- API doc templatetemplates/api_template.md
- User guide templatetemplates/guide_template.md
- Sample documentationexamples/
- Write SKILL.md that:
- References guidelines by doc type
- Uses progressive disclosure (only load needed guidelines)
- Provides workflow for each doc type
- Add examples for:
- API endpoint documentation
- User guide creation
- Architecture decision records
- Test with various documentation requests
Example 4: Extending an Existing Skill
User request:
Add spell correction to our transcribe skill
You would:
- Read current skill:
cat .claude/skills/transcribe/SKILL.md - Identify where to add the feature:
- After transcription step
- Before final output
- Create supporting file:
touch .claude/skills/transcribe/spell_corrections.md - Write correction mappings in new file:
# Spell Corrections - "cloud code" → "claude code" - "API" → "API" (ensure caps) ... - Update SKILL.md workflow:
- Add step: "Apply spell corrections from spell_corrections.md"
- Reference the corrections file
- Update examples to show correction step
- Test with audio that has common errors
Summary
Creating skills is about packaging expertise into discoverable, composable capabilities. Follow these principles:
- Read the docs first - Understand progressive disclosure and skill architecture
- Write clear descriptions - Include what AND when
- Keep instructions focused - Use supporting files for additional context
- Test thoroughly - Verify Claude discovers and uses the skill correctly
- Iterate with feedback - Refine based on actual usage
Skills transform general-purpose Claude into a specialist for your domain. Start small, test early, and expand as needed.