Claude Skills Practical Guide

Skills are instruction packages that Claude loads dynamically — a folder containing SKILL.md, scripts, and reference materials. When Claude detects a relevant task, it reads and follows these instructions automatically. This mechanism enables the same Claude to perform at specialist level across different domains.

As of the 2026-04-07 sync snapshot, Anthropic’s official repository contains 17 top-level Skills directories across four capability groups plus one meta skill.

Creative & Design

frontend-design

Breaks the “every AI page looks the same” pattern. Requires Claude to commit to a bold aesthetic direction before writing code — brutalist, retro-futuristic, maximalist, organic/natural, luxury/refined — then enforces that direction across typography, color, spacing, animation, and spatial composition. Explicitly bans overused fonts like Inter, Roboto, and Arial, forcing distinctive pairings. Supports HTML/CSS/JS, React, Vue, and other major frameworks.

Use cases: Websites, landing pages, dashboards, React components, or any frontend interface that needs elevated design quality.

/install anthropics/skills/frontend-design

canvas-design

Generates visual artwork on PDF or PNG canvases through code. Two-phase workflow: first outputs a “design philosophy” document (.md) defining the aesthetic movement’s core principles, then expresses it visually with original designs. Strictly avoids copying existing artists’ work.

Use cases: Poster design, cover art, data visualization graphics, brand visual assets.

/install anthropics/skills/canvas-design

algorithmic-art

Generates algorithmic art through p5.js: geometric patterns, flow fields, particle systems, and fractals. Outputs three file types: algorithmic philosophy document (.md), interactive viewer (.html), and generative algorithm (.js). Uses seeded randomness for reproducibility with interactive parameter exploration.

Use cases: Generative art creation, procedural visual assets, technical team branding elements.

/install anthropics/skills/algorithmic-art

theme-factory

Provides 10 curated professional theme systems, each with carefully selected color palettes and font pairings. Applicable to slides, docs, reports, HTML landing pages, or any artifact. Also supports on-the-fly theme generation from input keywords.

Use cases: Quick visual consistency for UI components, presentations, and marketing pages.

/install anthropics/skills/theme-factory

Document Processing

The four document Skills power Claude.ai’s document creation features (source-available license). Without them, Claude writes ad-hoc scripts for format handling with inconsistent results; with them, it follows production-tested standard pipelines.

docx

Create, read, and edit Word documents. Treats .docx as ZIP/XML structures under the hood, supporting table of contents generation, headers/footers, image insertion, tracked changes, find-and-replace, and other advanced features. Production output requires zero formatting errors.

Use cases: Technical reports, memos, contract templates, automated project documentation.

/install anthropics/skills/docx

xlsx

Complete pipeline for Excel and CSV/TSV files. Requires zero formula errors (no #REF!, #DIV/0!, etc.), professional fonts, chart generation, conditional formatting, and pivot table support. Handles messy raw data files with malformed rows and misplaced headers.

Use cases: Data cleaning, financial modeling, report generation, cross-format conversion.

/install anthropics/skills/xlsx

pdf

Full-lifecycle PDF processing: text extraction, merge/split, page rotation, watermarks, form filling, encryption/decryption, image extraction, and OCR for scanned documents. Built on Python toolchain (pypdf, pymupdf, etc.).

Use cases: Batch PDF processing, contract signing workflows, scanned document digitization.

/install anthropics/skills/pdf

pptx

Read, create, and edit PowerPoint presentations. Supports both template-based and from-scratch creation, handling master layouts, speaker notes, and comments. Integrates with markitdown for text extraction from .pptx files.

Use cases: Project reports, pitch decks, training materials, automated meeting presentations.

/install anthropics/skills/pptx

These four Skills chain naturally: extract from PDF → analyze in Excel → generate Word report → create PPT presentation.

Development & Technical

mcp-builder

Guides Claude through building production-quality MCP (Model Context Protocol) Servers. Covers the full four-phase workflow: deep API research, schema design, tool implementation, and evaluation testing. Recommends TypeScript + Streamable HTTP with complete reference implementations in both Python and TypeScript. Emphasizes tool naming discoverability, context management, actionable error messages, and tool annotations (readOnlyHint, destructiveHint, etc.).

Use cases: Integrating external APIs/services with Claude, building custom MCP Servers, expanding Claude’s tool ecosystem.

/install anthropics/skills/mcp-builder

claude-api

Build LLM-powered applications with the Claude API or Agent SDK. Auto-detects project language (Python / TypeScript / Java / Go / Ruby / C# / PHP / cURL) and loads matching code examples and SDK patterns. Includes model selection decision tree, Adaptive Thinking configuration (recommended for Opus 4.6 / Sonnet 4.6), Prompt Caching prefix-stability design, Compaction for long conversations, and Tool Runner automatic loop handling.

Use cases: Chatbots, multi-step workflows, custom agents, batch processing pipelines.

/install anthropics/skills/claude-api

webapp-testing

Playwright-based testing for local web applications. Provides with_server.py for server lifecycle management with multi-server parallel startup. Core pattern: reconnaissance-then-action — wait for networkidle, screenshot to identify selectors, then execute interactions. Includes example patterns: element discovery, static HTML automation, console log capture.

Use cases: Frontend functional verification, UI behavior debugging, browser screenshot comparison, automated regression testing.

/install anthropics/skills/webapp-testing

web-artifacts-builder

Build complex, multi-component web artifacts in Claude.ai. Stack: React 18 + TypeScript + Vite + Tailwind CSS + shadcn/ui. Initialize with init-artifact.sh, bundle into a single HTML file with bundle-artifact.sh. Designed for complex artifacts requiring state management, routing, or shadcn/ui components.

Use cases: Interactive prototypes, data dashboards, internal tool MVPs.

/install anthropics/skills/web-artifacts-builder

Enterprise & Collaboration

brand-guidelines

Loads official Anthropic brand colors and typography, applying them to any artifact — slides, docs, reports, HTML pages. Includes complete color system and type hierarchy definitions. Also serves as a template for creating similar brand guideline Skills for your own organization.

Use cases: Brand visual consistency, design specification documentation.

/install anthropics/skills/brand-guidelines

internal-comms

Drafts internal communications: 3P updates (Progress / Plans / Problems), all-hands emails, project updates, change notifications, incident reports, FAQs. Adjusts tone and information density based on audience level. Provides structured templates and best practice references.

Use cases: Leadership reports, cross-team notifications, project status updates, incident post-mortems.

/install anthropics/skills/internal-comms

doc-coauthoring

Structured collaborative document writing workflow. Three stages: Context Gathering (questions + info dump) → Iterative Refinement (per-section brainstorm → curate → draft → polish) → Reader Testing (validate with a context-free Claude to catch blind spots). Maintains document structure, cross-references, and terminology consistency.

Use cases: Technical white papers, product PRDs, design decision documents, RFCs, and other long-form documents requiring rigorous structure.

/install anthropics/skills/doc-coauthoring

slack-gif-creator

Creates animated GIFs optimized for Slack chat. Handles Slack’s size constraints (Emoji GIF 128×128, message GIF 480×480) with validation tools and animation concept templates.

Use cases: Custom team emojis, milestone celebration animations, fun communication assets.

/install anthropics/skills/slack-gif-creator

Meta Skill

skill-creator

Build your own Skills. Complete workflow: intent capture → user interview → SKILL.md drafting → test case generation → parallel comparison runs (with-skill vs without) → quantitative benchmarking → human review (via built-in HTML viewer) → iterative improvement → trigger description optimization (automated via run_loop.py). Supports progressive disclosure architecture: SKILL.md < 500 lines, large reference materials loaded on demand.

Use cases: Packaging team coding standards, deployment workflows, ops checklists, personal workflows — the domains that generic Skills don’t cover.

/install anthropics/skills/skill-creator

Installation

Claude Code (recommended)

Install individually in Claude Code:

/install anthropics/skills/frontend-design
/install anthropics/skills/mcp-builder
/install anthropics/skills/skill-creator
/install anthropics/skills/docx
# ... same pattern for other Skills

Claude.ai

Paid users have access to all official Skills without manual installation. Custom Skills are enabled by uploading .skill files.

Claude API

Attach Skills via the Skills API.

Loading Architecture

Skills use three-level progressive disclosure — installing many Skills doesn’t significantly increase per-session cost:

Triggering is based on semantic matching of the description field — Claude evaluates whether the current task needs a Skill’s specialized capabilities, loading full instructions only on match.

Next Steps