frontend

frontend is a skill for Claude Code, Codex from Joncik91/ucai. It costs 40 tokens per session (1,906 once invoked), scanned A, original, MIT.

A guide for building React interfaces and improving frontend applications. React is a JavaScript library for creating user interfaces from reusable components.

In plain words
What is it for?
Use it when creating React components, checking bundle size, improving loading speed, building accessible interfaces, reviewing frontend code, or redesigning a user interface.
Why use it?
It helps identify the project's frontend tools and address performance, accessibility, code quality, and visual design together.

Skill for Claude CodeCodex

Part of the ucai plugin — 8 skills, 10 commands, 8 agents, 8 hooks shipped together

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/joncik91/ucai/frontend
Any agent
npx skills add Joncik91/ucai --skill frontend
Clone the repo
git clone --depth 1 https://github.com/Joncik91/ucai

Made for: Claude Code, Codex.

Or install ucai, the plugin that ships this one along with the rest of its 8 skills, 10 commands, 8 agents, 8 hooks.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for frontend

README.md
[![agentmods](https://agentmods.dev/badge/skills/joncik91/ucai/frontend.svg)](https://agentmods.dev/skills/joncik91/ucai/frontend)
Your own site
<a href="https://agentmods.dev/skills/joncik91/ucai/frontend"><img src="https://agentmods.dev/badge/skills/joncik91/ucai/frontend.svg" alt="Measured on agentmods" height="20"></a>
Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,906 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00040 $0.01906
Opus 5 $0.00020 $0.00953
Sonnet 5 $0.00008 $0.00381
Haiku 4.5 $0.00004 $0.00191

Measured 5d ago against content hash 86dea44b7679, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

frontend scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/frontend/SKILL.md · 178 lines

How it starts

The opening of the file, as written. The whole thing — 178 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Frontend Engineer

Frontend development patterns, performance optimization, accessibility, and distinctive UI design for any framework.


Step 1: Detect the Stack

Before writing any code, identify the framework and tooling from project signals:

Signal file / pattern Stack
next.config.* Next.js (React)
nuxt.config.* Nuxt (Vue)
svelte.config.* SvelteKit
astro.config.* Astro
remix.config.* / @remix-run in package.json Remix (React)
angular.json Angular
vite.config.* + React Vite + React
vite.config.* + Vue Vite + Vue
tailwind.config.* Tailwind CSS
styled-components / emotion in package.json CSS-in-JS

Check: cat package.json, ls -la, cat vite.config.* — whichever applies.


Step 2: Research Current Practices

Once you know the stack, search before making framework-specific recommendations:

WebSearch: " component patterns best practices 2025" WebSearch: " performance optimization 2025" WebSearch: " bundle size optimization 2025" WebSearch: " accessibility best practices 2025" WebSearch: " best practices 2025"


Step 3: Design Thinking

First Principles preamble: before reaching for a library, framework, or component pattern, ask whether the choice solves this UI's specific constraint, or is a habit from larger apps. A landing page is not a dashboard; a settings panel is not a marketing site. Question the requirement before adopting the pattern; reject "we need X because everyone uses X" and reason from the actual user, content, and interaction model.

When building any UI — component, page, or application — commit to a bold aesthetic direction before writing a line of code:

  • Purpose: What problem does this interface solve? Who uses it?
  • Tone: Pick an extreme and own it. Brutally minimal, maximalist chaos, retro-futuristic, organic/natural, luxury/refined, playful/toy-like, editorial/magazine, brutalist/raw, art deco/geometric, soft/pastel, industrial/utilitarian — commit to one direction and execute it with precision.
  • Differentiation: What makes this unforgettable? What is the one thing someone will remember?
  • Constraints: Framework, performance budget, accessibility requirements.

Read the full file on GitHub · 178 lines

Files

What ships with it

4 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 5d ago First seen · 178 lines · 40 tokens per session scan A 86dea44b7679

Subscribe to this mod's changes

frontend is a skill published in the GitHub repository Joncik91/ucai (29 stars, last pushed 9d ago), licensed MIT. It adds 40 tokens to every session and 1,906 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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