official Anthropic skills
the 17 skills in anthropics/skills (115k+ stars) plus the skills bundled with Claude Code itself. these are the most reliable skills in the ecosystem — they come from the team that builds Claude.
bundled with Claude Code
these ship with every Claude Code install. always available, no setup:
| skill | what it does |
|---|---|
/simplify |
reviews recently changed code for reuse, quality, efficiency — then fixes |
/batch |
orchestrates large-scale changes across a codebase, 5-30 parallel worktree agents |
/debug |
structured debugging workflow |
/loop |
runs a prompt repeatedly on a schedule |
/claude-api |
loads Claude API + SDK reference |
the official repo
three installable plugins bundle the 17 skills:
document skills (source-available, proprietary license)
these power Claude's built-in document features. not open source, but you can read the code.
- docx — create, edit, analyze Word documents. tracked changes, comments, formatting, TOC. uses docx-js + XML.
- pdf — full PDF processing: extract, create, merge, split, watermark, OCR, encrypt, fill forms. uses pypdf.
- pptx — create, read, edit PowerPoint slides. uses pptxgenjs for creation, XML for editing.
- xlsx — spreadsheet manipulation: formulas, charts, data transformations. enforces professional formatting and color-coding (blue=inputs, black=formulas, green=cross-sheet links).
creative & design skills
- frontend-design — production-grade UI. explicitly bans generic "AI slop" aesthetics — picks bold aesthetic directions and executes with precision. 110k+ weekly installs, most popular skill in the ecosystem. see also design-and-frontend.
- algorithmic-art — generative art with p5.js: seeded randomness, flow fields, particle systems. outputs a "philosophy manifesto" then expresses it as HTML+JS sketches.
- canvas-design — visual art as PNG and PDF. two-step: design philosophy creation, then visual expression.
- web-artifacts-builder — complex claude.ai HTML artifacts with React 18 + TypeScript + Vite + Tailwind + shadcn/ui.
- theme-factory — 10 pre-set professional themes (color palettes + font pairings) for any artifact.
- brand-guidelines — Anthropic's official brand colors and typography.
- slack-gif-creator — animated GIFs optimized for Slack size constraints.
development & technical skills
- claude-api — build, debug, optimize apps with Claude API / Anthropic SDKs. covers Python, TypeScript, Ruby, Java, Go, PHP, C#, cURL. includes Managed Agents reference. the most extensively structured skill (8 language subdirectories).
- mcp-builder — guide for creating MCP servers in Python (FastMCP) or TypeScript (MCP SDK). see tooling.
- webapp-testing — test local web apps using Python Playwright. includes server lifecycle management, screenshots, DOM inspection. see development.
- skill-creator — meta-skill for creating, modifying, and benchmarking other skills. includes eval framework and description optimizer. see creating-skills.
enterprise & communication
- internal-comms — templates for 3P updates, newsletters, FAQs, status reports, incident reports.
- doc-coauthoring — three-stage co-authoring workflow: context gathering → iterative refinement → reader testing with a fresh Claude to catch blind spots. the only Apache 2.0 licensed communication skill.