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1. Specialized workflows - Multi-step procedures for specific domains
2. Tool integrations - Instructions for working with specific file formats or APIs
3. Domain expertise - Company-specific knowledge, schemas, business logic
4. Bundled resources - Scripts, references, and assets for complex and repetitive tasks

• Frontmatter (YAML): Configuration fields like

  name

  ,

  description

  ,

  context

  ,

  agent

  ,

  allowed-tools

  , etc. The

  description

  field is most important - Claude uses it to decide when to load the skill automatically.
• Body (Markdown): Instructions and guidance for using the skill. Only loaded AFTER the skill triggers (if at all).

• When to include: When the same code is being rewritten repeatedly or deterministic reliability is needed
• Example:

  scripts/rotate_pdf.py

  for PDF rotation tasks
• Benefits: Token efficient, deterministic, may be executed without loading into context
• Note: Scripts may still need to be read by Claude for patching or environment-specific adjustments

• When to include: For documentation that Claude should reference while working
• Examples:

  references/finance.md

  for financial schemas,

  references/mnda.md

  for company NDA template,

  references/policies.md

  for company policies,

  references/api_docs.md

  for API specifications
• Use cases: Database schemas, API documentation, domain knowledge, company policies, detailed workflow guides
• Benefits: Keeps SKILL.md lean, loaded only when Claude determines it's needed
• Best practice: If files are large (>10k words), include grep search patterns in SKILL.md
• Avoid duplication: Information should live in either SKILL.md or references files, not both. Prefer references files for detailed information unless it's truly core to the skill—this keeps SKILL.md lean while making information discoverable without hogging the context window. Keep only essential procedural instructions and workflow guidance in SKILL.md; move detailed reference material, schemas, and examples to references files.

• When to include: When the skill needs files that will be used in the final output
• Examples:

  assets/logo.png

  for brand assets,

  assets/slides.pptx

  for PowerPoint templates,

  assets/frontend-template/

  for HTML/React boilerplate,

  assets/font.ttf

  for typography
• Use cases: Templates, images, icons, boilerplate code, fonts, sample documents that get copied or modified
• Benefits: Separates output resources from documentation, enables Claude to use files without loading them into context

• README.md
• INSTALLATION_GUIDE.md
• QUICK_REFERENCE.md
• CHANGELOG.md
• etc.

1. Metadata (name + description) - Always in context (~100 words)
2. SKILL.md body - When skill triggers (<5k words)
3. Bundled resources - As needed by Claude (Unlimited because scripts can be executed without reading into context window)

• Form filling: See FORMS.md for complete guide
• API reference: See REFERENCE.md for all methods
• Examples: See EXAMPLES.md for common patterns

Claude loads FORMS.md, REFERENCE.md, or EXAMPLES.md only when needed.

**Pattern 2: Domain-specific organization**

For Skills with multiple domains, organize content by domain to avoid loading irrelevant context:

When a user asks about sales metrics, Claude only reads sales.md.

Similarly, for skills supporting multiple frameworks or variants, organize by variant:

When the user chooses AWS, Claude only reads aws.md.

**Pattern 3: Conditional details**

Show basic content, link to advanced content:

```markdown

1. Understand the skill with concrete examples
2. Plan reusable skill contents (scripts, references, assets)
3. Initialize the skill (run init-skill.ts)
4. Edit the skill (implement resources and write SKILL.md)
5. Package the skill (run package-skill.ts)
6. Iterate based on real usage

• "What functionality should the image-editor skill support? Editing, rotating, anything else?"
• "Can you give some examples of how this skill would be used?"
• "I can imagine users asking for things like 'Remove the red-eye from this image' or 'Rotate this image'. Are there other ways you imagine this skill being used?"
• "What would a user say that should trigger this skill?"

1. Considering how to execute on the example from scratch
2. Identifying what scripts, references, and assets would be helpful when executing these workflows repeatedly

pdf-editor

1. Rotating a PDF requires re-writing the same code each time
2. A

   scripts/rotate_pdf.py

   script would be helpful to store in the skill

frontend-webapp-builder

1. Writing a frontend webapp requires the same boilerplate HTML/React each time
2. An

   assets/hello-world/

   template containing the boilerplate HTML/React project files would be helpful to store in the skill

big-query

1. Querying BigQuery requires re-discovering the table schemas and relationships each time
2. A

   references/schema.md

   file documenting the table schemas would be helpful to store in the skill

init-skill.ts

bun scripts/init-skill.ts <skill-name> --path <output-directory>

• Creates the skill directory at the specified path
• Generates a SKILL.md template with proper frontmatter and TODO placeholders
• Creates example resource directories:

  scripts/

  ,

  references/

  , and

  assets/

• Adds example files in each directory that can be customized or deleted

• Multi-step processes: See references/workflows.md for sequential workflows and conditional logic
• Specific output formats or quality standards: See references/output-patterns.md for template and example patterns

description

• name

  : Display name (lowercase letters, numbers, hyphens, max 64 chars). If omitted, uses directory name.

• description

  : What the skill does and when to use it. Claude uses this to decide when to load the skill automatically.
  • Example: "Explains code with diagrams and analogies. Use when explaining how code works or when user asks 'how does this work?'"

• disable-model-invocation: true

  - Only user can invoke (prevents Claude auto-loading). Use for workflows with side effects like

  /deploy

  .

• user-invocable: false

  - Only Claude can invoke. Use for background knowledge that isn't actionable as a command.

• argument-hint

  : Hint shown during autocomplete. Example:

  [issue-number]

  or

  [filename]

• allowed-tools

  : Tools Claude can use without asking permission when skill is active.

• model

  : Model to use when skill is active.

• context: fork

  - Run in a forked subagent context (isolated, no conversation history).

• agent

  : Which subagent type to use when

  context: fork

  is set (e.g.,

  Explore

  ,

  Plan

  ,

  general-purpose

  , or custom agent).

• hooks

  : Hooks scoped to this skill's lifecycle.

• $ARGUMENTS

  - All arguments passed when invoking the skill

• ${CLAUDE_SESSION_ID}

  - Current session ID

---
name: deep-research
description: Research a topic thoroughly
context: fork
agent: Explore
---

Research $ARGUMENTS thoroughly:
1. Find relevant files using Glob and Grep
2. Read and analyze the code
3. Summarize findings with file references

bun scripts/package-skill.ts <path/to/skill-folder>

bun scripts/package-skill.ts <path/to/skill-folder> ./dist

1. Validate the skill automatically, checking:
   • YAML frontmatter format and required fields
   • Skill naming conventions and directory structure
   • Description completeness and quality
   • File organization and resource references
2. Package the skill if validation passes, creating a .skill file named after the skill (e.g.,

   my-skill.skill

   ) that includes all files and maintains the proper directory structure for distribution. The .skill file is a zip file with a .skill extension.

1. Use the skill on real tasks
2. Notice struggles or inefficiencies
3. Identify how SKILL.md or bundled resources should be updated
4. Implement changes and test again

• references/xml-tag-guide.md - Complete guide to XML tags and structure (required/conditional tags, nesting, naming conventions)
• references/progressive-disclosure-patterns.md - Advanced strategies for organizing content across multiple files
• references/prompting-integration.md - How to integrate expert prompting techniques into skills
• references/real-world-examples.md - Complete examples of well-structured skills (simple, standard, complex)
• references/script-patterns.md - Executable code patterns, error handling, script templates
• references/output-patterns.md - Template and example patterns for consistent output
• references/workflows.md - Sequential and conditional workflow patterns