Anthropic released a public repository containing example Skills - modular instruction sets that extend Claude's capabilities for specialized tasks. Skills are folders with markdown files that teach Claude to perform specific workflows like document creation, web testing, or brand-compliant design. The repository includes open-source examples across creative, technical, and enterprise categories, plus source-available document manipulation skills (DOCX, PDF, PPTX, XLSX) that power Claude's production features. Skills can be used in Claude Code, Claude.ai, and via API, with a simple YAML frontmatter structure for creating custom skills.