Claude apps (claude.ai) skills. Where they live and how to install them.

What skills are in the Claude apps

In claude.ai, a skill is a packaged folder of instructions, optional scripts and reference files that Claude uses when a task matches. Anthropic provides pre-built skills for Excel, Word, PowerPoint and PDF work. When code execution and file creation are on, Claude uses them automatically while you create documents. You can also upload your own custom skills.

There is no skills folder on your computer for claude.ai. You upload a ZIP file in the web or desktop app instead. Custom skills are tied to your account: skills you upload are not visible to colleagues until you share them, and they do not sync to the Claude API.

Requirements

• Code execution and file creation must be enabled. On Free, Pro and Max plans that is in Settings > Capabilities. On Team and Enterprise plans an owner enables it in Organization settings > Plugins & skills, on the Policy tab.
• Anthropic's Help Center says skills are available on the Free, Pro, Max, Team and Enterprise plans. Its API documentation lists Pro, Max, Team and Enterprise, so check Customize > Skills on your own plan.
• On Team and Enterprise, an owner can turn off user-created skills, in which case you can use provisioned skills but not upload your own.

Install a skill

The examples use frontend-design from anthropics/skills, located at skills/frontend-design.

Option 1: zip a skill folder you already have

The ZIP must contain the skill folder as its root, not loose files:

zip -r frontend-design.zip frontend-design/

The folder name should match the skill's name, and the folder must contain SKILL.md.

Option 2: build the ZIP from a GitHub repository

git clone --depth 1 https://github.com/anthropics/skills.git skills-src
cp -r skills-src/skills/frontend-design frontend-design
zip -r frontend-design.zip frontend-design
rm -rf skills-src

Then upload it

1. Open Customize > Skills.
2. Click the + button, then + Create skill.
3. Choose Upload a skill and select the ZIP.
4. Your skill appears in the list with a toggle. Turn it on.

Pre-built example skills are also listed on the same page, where you can switch them on without uploading anything.

Check that it loaded

Open Customize > Skills and confirm the skill is listed and switched on. Then try a prompt that matches its description and look at Claude's reasoning to see whether it loaded the skill. Disabled skills are not available to Claude. On Team and Enterprise plans, your list is grouped into sections such as personal skills and organization skills.

Share, update and remove

• Update: the Help Center does not describe replacing an upload in place, so delete the old copy and upload the new ZIP.
• Remove: open Customize > Skills, click the skill, switch it off, then use the ... button next to the toggle and choose Delete. To bring it back, upload the file again.
• Share: on Team and Enterprise, owners must first allow sharing. Then you can share a skill with colleagues or groups, or publish it to the organization's library. Shared skills are view-only for recipients, and owners can also provision skills for everyone.
• Claude Code: skills you enable here also download into Claude Code when you sign in with the same account (Claude Code 2.1.273 or later).

Troubleshooting

• Upload fails: the Help Center lists a ZIP over the size limit, a folder name that does not match the skill name, a missing skill file, and invalid characters in the name or description.
• The ZIP has the wrong shape: if the files sit at the root of the archive rather than inside a folder, repackage it so the folder is the root.
• Name rules: Anthropic's documentation says a name cannot contain the reserved words anthropic or claude, and the API documentation limits names to lowercase letters, numbers and hyphens.
• Limits disagree between pages: the Help Center's upload guide cites a 64-character name and a 200-character description and calls the file skill.md, while the open standard and the API documentation use SKILL.md and allow 1,024 characters. Keep the description short and use SKILL.md, as public skill repositories do, then read the error message if an upload is rejected.
• Skills are greyed out or missing: check that code execution is enabled for you, or ask your organization owner on Team and Enterprise.

Safety

Skills can carry scripts, and in claude.ai they run in Claude's code execution environment. Network access there depends on your own and your organization's settings. Review SKILL.md and every bundled file before you upload a skill you did not write. Anthropic recommends using skills only from sources you trust. On Enterprise plans an organization can turn on skill scanning, which checks third-party skills for malicious content before they can run.