Creating Custom Skills

Creating Custom Skills

Links to Custom Skills

• analyzing time series
• generating practice questions

References

For a complete list of Skills creation best practices and specification, make sure to check out:

• Skill authoring best practices
• Specification
• The Complete Guide to Building Skills for Claude

How to Disable Plugins in Claude Code?

Plugins are designed to toggle on and off as needed. You can enable them when you need specific capabilities and disable them when you don't to reduce system prompt context and complexity.

• Using the /plugin Command: navigate to installed tab, then select the plugin you want to disable.
• Using the command line: claude plugin disable <plugin-name>

Summary of the Slides

SKILL.md File Structure

A skill file has two main parts:

1. YAML Frontmatter — Metadata at the top
2. Body Content — Markdown instructions below

Frontmatter Required Fields

Frontmatter Optional Fields

Body Content

No format restrictions, but here are some recommendations:

Recommended Sections

• Step-by-step instructions
• Input Format / Output Format / Examples
• Common edge cases

Practical Guidance

• Keep it under 500 lines
• Move detailed reference material to separate files (show basic content, link to advanced content)
• Keep references one level deep from SKILL.md (avoid nested file references)
• Be clear and concise, use consistent terminology
• Use forward slashes in file paths, even on Windows

Degrees of Freedom

Complex Workflows

• Break complex operations into clear, sequential steps
• If workflows become large with many steps, consider pushing them into separate files

Optional Directories

/assets

• Templates: document templates, configuration templates
• Images: diagrams, logos
• Data files: lookup tables, schemas

/references

• Contains additional documentation that agents can read when needed
• Keep individual reference files focused
• Note: For reference files longer than 100 lines, include a table of contents at the top so the agent can see the full scope

/scripts

• Clearly document dependencies
• Scripts should have clear documentation
• Error handling should be explicit and helpful
• Note: Make clear in your instructions whether Claude should execute the script or read it as reference

Evaluation

Unit Tests

Define test cases with:

• skills: Which skills to test
• queries: Test prompts to run
• files: Input files to use
• expected_behavior: What success looks like

Example Test Case

{
  "skills": ["generating-practice-questions"],
  "queries": [
    "Generate practice questions from this lecture note and save it to output.md",
    "Generate practice questions from this lecture note and save it to output.tex",
    "Generate practice questions from this lecture note and save it to output.pdf"
  ],
  "files": ["test-files/notes.pdf", "test-files/notes.tex", "test-files/notes.pdf"],
  "expected_behavior": [
    "Successfully reads and extracts the input file. For pdf input, uses pdfplumber.",
    "Successfully extracts all the learning objectives.",
    "Generates the 4 types of questions.",
    "Follows the guidelines for each question.",
    "Uses the output structure and the correct output templates.",
    "The latex output successfully compiles.",
    "Saves the generated questions to a file named output."
  ]
}

Additional Evaluation Tips:

• Get human feedback
• Test with all the models you plan to use