Claude Code Skills, Plugins and MCP Servers Worth Installing

Every week there is a new list of 50 Claude skills you supposedly need. Most people install a dozen, feel productive for a day, and then wonder why Claude got slower and less focused. The setups that work best are small. I build my apps with Claude Code every day, and the things I actually keep installed fit on one screen.

This guide gives you a short, verified starting set, the exact commands to install it, and a simple way to decide what stays.

Know what you are installing

Three kinds of add-ons show up in every list, and they do different jobs.

• Skill: a folder with a SKILL.md file that teaches Claude one workflow. Claude reads the name and description of every skill in each session and loads the full instructions when a task matches, or when you type /skill-name.
• Plugin: a package that can bundle skills, agents, hooks and MCP servers. You install plugins from a marketplace, which is just a catalog hosted in a Git repo.
• MCP server: a connection to an outside tool or service, like GitHub, Notion or a browser. It gives Claude access, not knowledge.

That last point matters. Installing a Notion skill does not let Claude read your Notion. Connecting the Notion MCP server does.

Start with the official marketplace

Claude Code adds Anthropic's official marketplace, claude-plugins-official, the first time you start it. Open the plugin manager and look at the Discover tab before you go searching on GitHub:

/plugin

You can also browse the same catalog on the web at claude.com/plugins. When the plugin manager asks for a scope, pick user scope for tools you want everywhere and project scope for tools your whole team should get from the repo.

The starting set I recommend

These are all real, all maintained, and cover the jobs most people actually do.

skill-creator

The most useful skill is the one you write yourself. skill-creator helps you turn a workflow you repeat into your own skill, and test whether it triggers when it should.

/plugin install skill-creator@claude-plugins-official

frontend-design

If you build anything with a UI, this is Anthropic's skill for pushing Claude toward a clear visual direction instead of the default template look.

/plugin install frontend-design@claude-plugins-official

Document skills

Anthropic's skills repo ships a plugin that creates and edits real Word, Excel, PowerPoint and PDF files. Add the marketplace once, then install:

/plugin marketplace add anthropics/skills
/plugin install document-skills@anthropic-agent-skills

On claude.ai and the desktop app you do not need this. The same document skills are built in when code execution is on, and you manage skills under Customize, then Skills.

context7

Claude's knowledge of a library can lag behind the version you use. The context7 plugin connects a documentation server so Claude can look up current docs while it writes code.

/plugin install context7@claude-plugins-official

playwright

This gives Claude a real browser. It can open your local page, click through it and take screenshots, which means it can check its own work instead of guessing.

/plugin install playwright@claude-plugins-official

One integration for where your work lives

Pick the one service you touch most. The official marketplace has plugins for github, linear, notion, slack, figma, sentry and more. One is enough to start.

/plugin install github@claude-plugins-official

Community skills: read before you install

Some of the best skills come from individuals. humanizer, which strips common AI writing patterns out of drafts, is a good example. But a community skill is someone else's instructions and scripts running with your permissions, so treat it like any code you pull from the internet.

My routine is simple. Clone it, read the SKILL.md and every other file in the folder, then copy it into your personal skills directory:

git clone https://github.com/blader/humanizer /tmp/humanizer
less /tmp/humanizer/SKILL.md
mkdir -p ~/.claude/skills
cp -R /tmp/humanizer ~/.claude/skills/humanizer

Skills in ~/.claude/skills/ work in all your projects. Skills in a repo's .claude/skills/ folder work only in that repo, and your team gets them once you commit the folder. Claude Code notices new skill folders during a session. If the skills directory itself did not exist when you started, restart once.

Many repos also support the open source skills CLI, which does the copying for you with npx skills add owner/repo. It is convenient. Read the repo first anyway.

Connecting apps with MCP

If a service is not available as a plugin, add its MCP server directly. For a remote server, it is one line:

claude mcp add --transport http notion https://mcp.notion.com/mcp

Then run /mcp inside Claude Code to sign in. On claude.ai the equivalent lives under Customize, then Connectors. Before you connect anything with write access, check what the connection can change. Read access is usually all you need for the first week.

Prove each install on a real task

Install one thing, then give it a job you already know the answer to. That tells you in five minutes whether it earns its place. I use a prompt like this:

I just installed [plugin or skill name]. Before we use it for real:
1. Tell me in two sentences what it adds and what it can access.
2. Run it on this small task: [task with a known good result].
3. Show me the output next to what I expected and point out any
   guesses you made.
Do not connect other accounts, send messages or publish anything.

If the result is not better than what you got without it, uninstall it. A tool that only looks useful still costs you something.

Keep the setup lean

Every installed skill adds its name and description to Claude's context on every turn. Plugins with MCP servers add more. That cost is small per item and real in total, and a long list also makes it harder for Claude to pick the right skill.

• Run /plugin and open the Installed tab. Disable anything you have not used in two weeks. Claude Code marks plugins it has not seen you use.
• Run /skill-doctor to see what each skill costs in context and how often it runs.
• Run /context when a session feels sluggish to see what is taking up space.

Start with skill-creator and one tool that matches your main job. Use them for a week. Then write your first own skill for the task you explained to Claude most often that week. That skill will be worth more than anything on a list of 50.