Skills and plugins, in one breath
Skills are markdown instruction packs (SKILL.md files) that
teach Claude a specialized workflow — reviewing for security issues, designing frontend,
writing clean commits. Claude activates them automatically when they're relevant to the
task. Plugins are the installable packages that bundle skills — plus,
optionally, slash commands, agents, hooks and even MCP servers. Think of plugins as apps,
skills as the knowledge inside them.
Installing from the official marketplace
The official Anthropic marketplace (claude-plugins-official) is built in —
nothing to add. Inside a session:
/plugin ← opens the manager (Discover / Installed / Marketplaces / Errors)
/plugin install frontend-design@claude-plugins-official
/reload-plugins ← apply changes without restartingBefore you confirm an install, the details pane shows two things worth actually reading: a context-cost estimate (how many tokens the plugin adds to every message) and exactly what it will install. Then choose a scope: User for things you want in every project, Project for repo-specific ones.
The starter set
Six earn their keep for a beginner building websites — install these, skip the rest for now:
| Plugin | Why a beginner web-dev wants it |
|---|---|
frontend-design | Better, less-generic UI output when building pages and components |
commit-commands | Clean git commit/push/PR workflows as slash commands |
security-guidance | Reviews Claude's own changes for common vulnerabilities as it works — training wheels you'll want even as a pro |
code-simplifier | Refactoring passes that keep AI-generated code readable |
feature-dev | A structured workflow for larger features (plan → build → verify) |
context7 | Fetches up-to-date library documentation mid-task (also exists as an MCP — either form is fine) |
The rule: every installed plugin costs context on every turn. Four to six sharp picks beat twenty. There's also a community marketplace (/plugin marketplace add anthropics/claude-plugins-community) with validated third-party plugins, and thousands more across the ecosystem — explore later, not on day one.
Write your own micro-skill (ten minutes, surprisingly powerful)
The moment you notice yourself repeating the same instructions — "every page needs a meta
description", "always run the build before finishing" — turn them into a skill. Create
.claude/skills/my-site-rules/SKILL.md in your project:
---
name: my-site-rules
description: Conventions for this website. Use when creating or editing any page or component.
---
- Every new page must include: canonical URL, meta description, OG image.
- Components: PascalCase files. No new client-side frameworks.
- After any change: run `npm run build` and report errors before finishing.That's the entire format — frontmatter saying when it applies, then the rules. Now every page Claude ever builds follows your standards without being told. This is how you scale yourself, not just the tool.
Up next: skills give Claude knowledge; MCP servers give it capabilities — a real browser, your GitHub, your database. And capabilities need discipline.