Skills
What Skills Are
Section titled “What Skills Are”Skills are folders containing instructions, scripts, and resources that the AI discovers and loads dynamically when relevant to a task. They encapsulate a specific capability — instructions, context, and output format bundled together — so you don’t have to re-explain the same task every time.
Skills are now an open standard and being adopted broadly across platforms. Think of them as upgraded prompts: they package a prompt with its context into something reusable, shareable, and automatically invocable.
Key Characteristics
Section titled “Key Characteristics”- Encapsulates a specific capability — instructions, context, and output format bundled together
- Dynamically loaded or directly invoked — the AI discovers and loads skills automatically when relevant, or you invoke them with a slash command (
/plugin-name:command) - Reusable across conversations — write once, use every time the task comes up
- Shareable — skills can be distributed to others through plugins or file sharing
- Becoming an open standard — the skill format is being adopted across compatible platforms
When to Use a Skill
Section titled “When to Use a Skill”Use a skill when:
- You find yourself writing the same prompt repeatedly
- A workflow step is well-defined enough to package as a repeatable routine
- Consistency matters — the output should follow the same structure every time
- You want others to be able to run the same task with the same quality
A good rule of thumb: if you give an AI the same instructions more than three times, it’s time to package those instructions as a skill.
Anatomy of a Skill
Section titled “Anatomy of a Skill”A skill is a folder containing:
skill-name/├── SKILL.md # Instructions — what the skill does and how└── references/ # Optional context files the skill needs ├── style-guide.md └── template.mdThe SKILL.md file contains the instructions. The references/ folder holds any context the skill needs — style guides, templates, examples, or data.
On Claude Code, skills with user_invocable: true and a command: field in their frontmatter can be invoked directly as slash commands.
Platform Implementations
Section titled “Platform Implementations”Agent Skills are an open standard — the same SKILL.md format works across platforms. Each platform reads skill files from its own directory, but the file format is identical.
Not every platform supports skills natively yet. This table shows you what to expect:
| Platform | Skill Support | Skill Directory / How It Works | Notes |
|---|---|---|---|
| Claude.ai (web) | ✅ Native | Uploaded via Settings | ZIP upload under Settings > Capabilities > Upload skill. Skills uploaded here are also available in Claude Cowork |
| Claude Cowork | ✅ Native | Shared with Claude.ai, plus plugin system | Uses the same skills you upload to Claude.ai; also install plugins via + > Add plugins |
| Claude Code | ✅ Native | .claude/skills/ | Also installable via plugins (/plugin install) |
| M365 Copilot Cowork | ✅ Native | OneDrive: Documents/Cowork/Skills/ | Frontier preview; auto-discovered each conversation; up to 20 skills, 1 MB per SKILL.md |
| OpenAI Codex (CLI, desktop, IDE) | ✅ Native | .agents/skills/ | Same SKILL.md format |
| ChatGPT | 🟡 Beta | Native skills rolling out on some plans | Use Projects as a workaround on plans without native skill support |
| Gemini CLI / Antigravity | ✅ Native | .gemini/skills/ or .agents/skills/ | Same SKILL.md format |
| Google Gemini (app) | ❌ No support | — | Use Gems or paste SKILL.md contents into the prompt |
| Gemini Enterprise | ❌ No support | — | Use Gems or paste SKILL.md contents into the prompt |
| Cursor | ✅ Native | .cursor/skills/, .claude/skills/, .codex/skills/, or .agents/skills/ | Reads from Claude Code and OpenAI Codex directories too — no need to move files |
| VS Code Copilot | ✅ Native | .github/skills/ or .agents/skills/ | Same SKILL.md format |
Legend: ✅ Native = platform officially supports Agent Skills. 🟡 Beta = native support exists but is limited. ❌ No support = no native skill feature; use a workaround like pasting SKILL.md into a Gem or prompt.
Where Skills Run
Section titled “Where Skills Run”The same SKILL.md format works everywhere, but the execution environment differs. Two factors matter:
1. Where the Skill executes — in a vendor-managed sandbox, or on your local machine 2. What it can access — only files you upload, or your full filesystem
| Platform | Where Files Live | Execution Environment | Filesystem Access |
|---|---|---|---|
| Claude.ai (web) | Cloud (uploaded ZIP) | Cloud sandbox | Uploaded files only |
| Claude Cowork | Cloud (shared with Claude.ai + plugin marketplace) | Cloud sandbox | Uploaded files only |
| Claude Code (Desktop + Terminal) | Local (.claude/skills/) | Your machine | Full local filesystem |
| Cursor | Local (.cursor/skills/ or .agents/skills/) | Your machine | Full local filesystem |
| OpenAI Codex CLI | Local (.agents/skills/) | Your machine | Full local filesystem |
| Gemini CLI | Local (.gemini/skills/ or .agents/skills/) | Your machine | Full local filesystem |
| VS Code Copilot | Local (.github/skills/ or .agents/skills/) | Your machine | Full local filesystem |
| M365 Copilot Cowork (Frontier preview) | OneDrive (Documents/Cowork/Skills/) | Microsoft cloud | OneDrive only |
What this means for what you can build:
-
Cloud-execution Skills (Claude.ai, Cowork, M365 Copilot Cowork) excel at document creation, research, analysis, and anything where the AI works on content you provide in the conversation. They can’t read your local files, run commands on your machine, or touch your local development environment.
-
Local-execution Skills (Claude Code, Cursor, OpenAI Codex, Gemini CLI, VS Code Copilot) can read and write your actual project files, run terminal commands, integrate with local tools, and operate on your filesystem. Required for any workflow that needs to touch files outside the chat window.
The pragmatic default:
| If you want to… | Build Skills for… |
|---|---|
| Create docs, slides, reports, research output | Claude.ai or Claude Cowork |
| Work on code or files in a project | Claude Code, Cursor, or OpenAI Codex |
| Operate inside Microsoft 365 | M365 Copilot Cowork |
| Maximize portability across local AI tools | .agents/skills/ (works in Cursor, OpenAI Codex, Gemini CLI, VS Code Copilot) |
For full per-platform setup instructions, see the AI Workflow Framework Skills setup guide.
How to Install Skills
Section titled “How to Install Skills”Each platform has its own install path. Pick yours — these pages link out to the official vendor docs for step-by-step instructions:
| Platform | Skills setup |
|---|---|
| Claude (web, Cowork, Code) | Installing Skills on Claude |
| M365 Copilot Cowork | Skills on M365 Copilot |
| OpenAI (Codex + ChatGPT) | Skills on OpenAI |
| Google Gemini (CLI, app) | Skills on Google Gemini |
| Cursor | Skills on Cursor |
VS Code Copilot and other editors: Drop the skill folder into .github/skills/. Use .agents/skills/ to share skills across Cursor, OpenAI Codex CLI, Gemini CLI, and VS Code Copilot from one location.
Skill, Project, or Prompt?
Section titled “Skill, Project, or Prompt?”| Approach | Best For | Example |
|---|---|---|
| Prompt | One-off or infrequent tasks | ”Summarize this PDF” |
| Project | Recurring context without rigid steps | Client research workspace |
| Skill | Repeatable process with consistent format and standards | Weekly status report generation |
Guides
Section titled “Guides”| Guide | Description |
|---|---|
| Discover Your Best Claude Skills | Guided process to identify your highest-value skill candidates |
| The Complete Guide to Building Skills for Claude | Anthropic’s official guide covering skill structure, best practices, and advanced patterns |
| Improving skill-creator: Test, measure, and refine Agent Skills | How to test, measure, and iteratively refine skills using the skill-creator workflow |
Related
Section titled “Related”- Agentic Building Blocks — Skills in the context of all building blocks
- AI Use Cases — what teams build with skills, organized by six primitives
- Prompts — the foundation that skills build on
- Agents — autonomous systems that invoke skills as part of multi-step workflows
- Agents & Skills — pre-built skills you can download or install