12 open-source picks that make the UI look designed, keep the code small, cut token use and give the agent fresh docs and a real browser.
See all 12 picksWorks with Claude Code · Codex · Cursor · Gemini CLI · Copilot
By Yovan · Updated
Twelve stops, one route. Hover a stop to see what it does, click to jump to it.Twelve stops, one route. Scroll to walk the trail, tap a stop to jump to it.
Yo Skills
Field Guide
| Your problem | Install | Stop |
|---|---|---|
| My UI looks AI-generated | Frontend Design + Impeccable | 01 |
| I want a bold, opinionated design | Taste Skill | 02 |
| The agent writes too much code | Ponytail | 05 |
| I hit usage limits too fast | Caveman | 06 |
| It codes before it thinks | Superpowers | 07 |
| It uses outdated APIs | Context7 | 09 |
| I want it to test its own UI | Playwright MCP | 10 |
| I need to debug a slow page | Chrome DevTools MCP | 11 |
More to be added
Grouped by what they fix. /plugin is Claude Code only; npx skills add and MCP work in other agents too.
Rules that stop AI-built UI from looking generated.
Skill 01 · Anti-slop
About
Audits and polishes a UI, and flags common AI-slop patterns.
Made by pbakaus · open source
Why it helps
Catches purple gradients, glows, bounce easing and side-tab borders.
Best for
A UI that works but looks generated.
Install
npx skills add pbakaus/impeccableSkill 02 · Anti-slop
About
A frontend taste framework with a stricter anti-slop mode.
Made by Leonxlnx · open source
Why it helps
Moves layout, type and spacing off template defaults.
Best for
New landing pages.
Install
npx skills add Leonxlnx/taste-skillSkill 03 · Official
About
Anthropic's official skill for distinctive, production-grade UI.
Made by Anthropic · open source
Why it helps
Small, official, the safe first install.
Best for
Your first UI project with an AI agent.
Install
/plugin install frontend-design@claude-plugins-officialSkill 04 · Reference
About
A searchable library of styles, palettes and font pairings.
Made by nextlevelbuilder · open source
Why it helps
Real palettes and type pairs instead of guesses.
Best for
Projects with no design direction yet.
Install
npx skills add nextlevelbuilder/ui-ux-pro-max-skillLess new code, more planning, fewer tokens.
Skill 05 · Minimal code
About
Reuses existing code and the standard library before writing new code.
Made by DietrichGebert · open source
Why it helps
Smaller diffs, fewer helpers nobody asked for.
Best for
Codebases where the agent reinvents utilities.
Install
/plugin marketplace add DietrichGebert/ponytailSkill 06 · Fewer tokens
About
Short, stripped-down replies. Code and terms stay exact.
Made by JuliusBrussee · open source
Why it helps
Fewer output tokens, longer sessions.
Best for
Long sessions and tight usage limits.
Install
claude plugin marketplace add JuliusBrussee/cavemanSkill 07 · Workflow
About
Skills for planning, test-driven work and systematic debugging.
Made by obra · open source
Why it helps
Stops the agent from coding before it thinks.
Best for
Features that touch several files.
Install
/plugin install superpowers@claude-plugins-officialSkill 08 · Official
About
Write, test and tune your own skills.
Made by Anthropic · open source
Why it helps
Turns repeated instructions into a reusable skill.
Best for
Teams with their own conventions.
Install
/plugin marketplace add anthropics/skillsFresh docs and a real browser for the agent.
Skill 09 · Docs
About
Pulls current, version-specific docs into the prompt.
Made by Upstash · open source
Why it helps
Fewer made-up or outdated APIs.
Best for
Next.js, React, Tailwind and other fast movers.
Install
claude mcp add context7 -- npx -y @upstash/context7-mcp@latestSkill 10 · Browser
About
Lets the agent open pages, click and fill forms.
Made by Microsoft · open source
Why it helps
It checks its own UI work.
Best for
End-to-end testing after a change.
Install
claude mcp add playwright -- npx @playwright/mcp@latestSkill 11 · Debug
About
Console, network, performance traces and screenshots from Chrome.
Made by Chrome DevTools · open source
Why it helps
Real data for slow pages and errors.
Best for
Debugging and performance.
Install
claude mcp add chrome-devtools -- npx chrome-devtools-mcp@latestSkill 12 · Official
About
Reads and creates PDF, Word, Excel and PowerPoint files.
Made by Anthropic · open source
Why it helps
Reports and decks from one prompt.
Best for
Turning notes into documents.
Install
/plugin install document-skills@anthropic-agent-skillsShort answer: Frontend Design + Impeccable for UI, Ponytail for leaner code, Caveman for fewer tokens, Superpowers for planning, Context7 for docs, Playwright MCP for testing.
A skill is a folder with a SKILL.md file: instructions, and sometimes scripts or reference files, that teach the agent one way of working. It is an open standard: Claude Code, Codex, Cursor, Gemini CLI and GitHub Copilot all read the same format. The agent reads only the short description at the start of a session and loads the full skill when a task matches, so installed skills cost almost nothing until they are used.
The easiest way to install one is npx skills add owner/repo, which puts it in the right folder for each agent you use. In Claude Code, skills also come bundled in plugins that you install with /plugin. An MCP server is different: it is a running program that gives the agent new tools, such as a browser or a documentation search, and it works in any agent that supports MCP.
The list above is short on purpose. Every pick fixes a specific problem I ran into while building with AI coding agents, and each one is open source, so you can read exactly what it tells the agent before you install it.
Three steps. No account, no config files to write by hand.
01.
Step 01 of 03
Ugly UI, bloated code or burned tokens. Start with the one that bugs you most.
02.
Step 02 of 03
Paste it in your terminal. npx skills add works for most agents; /plugin is Claude Code only.
03.
Step 03 of 03
Open a new session and ask as usual. Skills load when the task matches.
Short answers to what people usually ask.
A skill is a folder with a SKILL.md file of instructions, and sometimes scripts or reference files, that an AI coding agent loads when a task matches the skill's description. SKILL.md is an open standard, so the same skill works in Claude Code, Codex, Cursor, Gemini CLI and GitHub Copilot and many other agents. It teaches the agent a way of working, like a design checklist, a coding style or a file format.
The quickest way is npx skills add owner/repo: it detects the agents you have and installs the skill for them, or pick one with -a, for example -a codex. In Claude Code many skills also install as plugins with /plugin. You can also copy the skill folder into your agent's skills folder by hand. Start a new session afterwards.
A skill is instructions the agent reads. An MCP server is a running tool the agent can call, like a browser or a documentation search. Skills change how the agent works; MCP servers give it new abilities.
Start with Anthropic's official Frontend Design skill. For stricter rules against generic AI design, add Impeccable or Taste Skill. If you have no design direction at all, UI/UX Pro Max gives the agent palettes and font pairings to choose from.
Install a design skill such as Impeccable or Taste Skill, give the agent a reference (a site you like, a color, a font), and ask it to avoid purple gradients, glowing cards and centered-everything layouts. Then have it check the result in a real browser with Playwright MCP.
Ponytail is an open-source coding-agent skill by DietrichGebert that makes the agent reuse existing code, the standard library and native platform features before writing new code. It has lite, full and ultra modes.
Caveman is an open-source skill by JuliusBrussee that makes the agent answer in short, stripped-down sentences while keeping code and technical terms exact. The goal is fewer output tokens and less reading.
Yes, mostly. Skills follow the open SKILL.md standard, which Claude Code, Codex, Cursor, Gemini CLI and GitHub Copilot all support, and npx skills add installs them for each agent. The MCP servers work in any MCP-compatible client. A few install commands on this page are Claude Code plugin commands (/plugin); check each README for the setup in your agent.
Every item on this list is open source and free to install. You still pay for your own model usage.
Frontend Design plus Impeccable is the fastest visible upgrade. Add the rest when you need them.
Start with design