20-frontend-ui

20-frontend-ui is a cursor rule for Cursor from Mazalucas/El-DT-Lightweight-Army. It costs 0 tokens per session (410 once invoked), scanned A, original, MIT.

A set of frontend rules for building web interfaces, with guidance on components, state, accessibility, performance, and reuse. It gives React and Vite as the default for new web projects but says to respect an existing stack.

In plain words
What is it for?
Use it when creating or changing React components, managing interface state, adding keyboard and screen-reader support, or improving loading and rendering performance.
Why use it?
It helps keep user-interface code consistent, accessible, maintainable, and free from duplicated components.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/.

Good fit Use it when creating or changing React components, managing interface state, adding keyboard and screen-reader support, or improving loading and rendering performance.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/mazalucas/el-dt-lightweight-army/20-frontend-ui
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.

Clone the repo
git clone --depth 1 https://github.com/Mazalucas/El-DT-Lightweight-Army

Made for: Cursor.

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 20-frontend-ui

README.md
[![agentmods](https://agentmods.dev/badge/rules/mazalucas/el-dt-lightweight-army/20-frontend-ui/github.svg)](https://agentmods.dev/rules/mazalucas/el-dt-lightweight-army/20-frontend-ui)
Your own site
<a href="https://agentmods.dev/rules/mazalucas/el-dt-lightweight-army/20-frontend-ui"><img src="https://agentmods.dev/badge/rules/mazalucas/el-dt-lightweight-army/20-frontend-ui/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for 20-frontend-ui

Your own site · 80×15
<a href="https://agentmods.dev/rules/mazalucas/el-dt-lightweight-army/20-frontend-ui"><img src="https://agentmods.dev/badge/rules/mazalucas/el-dt-lightweight-army/20-frontend-ui.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 0 Nothing until a file matches its globs; then the whole rule loads.
When invoked 410 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 5.1 $0.00000 $0.00410
Opus 5 $0.00000 $0.00205
Sonnet 5 $0.00000 $0.00082
Haiku 4.5 $0.00000 $0.00041

Measured 7d ago against content hash 423a0f350228, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

20-frontend-ui 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 7d 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.

.cursor/rules/20-frontend-ui.mdc · 53 lines

What it actually says

Frontend y UI

Stack default del DT: ver regla 08-stack-web-default y vitals/data/engineering/web-stack.yaml.

Stack default (proyecto web nuevo)

  • Bundler: Vite
  • UI: React (componentes funcionales)
  • Backend client: Firebase JS SDK modular (v9+)
  • Alternativas permitidas: React solo, Vite solo — según web-stack.yaml

Si el repo ya usa otro framework, respetarlo (soft default).

Componentes

  • Usar componentes funcionales
  • Extraer hooks para lógica reutilizable
  • Colocar estilos cerca de componentes
  • Preferir composición sobre herencia

Estado

  • Estado local para UI; estado global solo cuando cruza muchos componentes
  • Evitar prop drilling excesivo; considerar context o state management

Accesibilidad

  • Atributos ARIA cuando sea necesario
  • Labels en formularios
  • Contraste de colores
  • Navegación por teclado

Performance

  • Lazy load de rutas/componentes pesados
  • Memoización cuando el costo de re-render es alto
  • Imágenes optimizadas

Reutilización (reuse-first)

Regla transversal: 15-engineering-reuse · skill frontend · DOC-REF-006.

  • No duplicar componentes — buscar en components/, ui/, hooks existentes; variant props antes de archivo nuevo
  • Tokens semánticos del design system o Atelier — no hex sueltos si hay handoff
  • Handoff Atelier: implementar component-specs tal cual (skill frontend/references/atelier-handoff.md)
  • Composición sobre copiar markup entre páginas
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. 7d ago First seen · 53 lines · 0 tokens per session scan A 423a0f350228

Subscribe to this mod's changes

20-frontend-ui is a cursor rule published in the GitHub repository Mazalucas/El-DT-Lightweight-Army (4 stars, last pushed 1mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 410 tokens. 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 2026-09-03.