Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/juandoroteoflesiauni-lang/Market-options-stocks-Scannernpx agentmods add rules/juandoroteoflesiauni-lang/market-options-stocks-scanner/03-frontend-nextjsWrote 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.
[](https://agentmods.dev/rules/juandoroteoflesiauni-lang/market-options-stocks-scanner/03-frontend-nextjs)<a href="https://agentmods.dev/rules/juandoroteoflesiauni-lang/market-options-stocks-scanner/03-frontend-nextjs"><img src="https://agentmods.dev/badge/rules/juandoroteoflesiauni-lang/market-options-stocks-scanner/03-frontend-nextjs/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.
<a href="https://agentmods.dev/rules/juandoroteoflesiauni-lang/market-options-stocks-scanner/03-frontend-nextjs"><img src="https://agentmods.dev/badge/rules/juandoroteoflesiauni-lang/market-options-stocks-scanner/03-frontend-nextjs.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00000 | $0.01391 |
| Opus 5.5 | $0.00000 | $0.00556 |
| Sonnet 5.5 | $0.00000 | $0.00278 |
| Haiku 4.5 | $0.00000 | $0.00139 |
Grade A, and why
03-frontend-nextjs scanned grade A with 1 finding 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 1mo 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.
Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
const response: any = await fetch(url) How it starts
The opening of the file, as written. The whole thing — 189 lines — stays where its author put it; the contents beside it link to each section on GitHub.
⚡ FRONTEND NEXT.JS 16 — ESTÁNDARES v3.0
FASE LOCK ACTIVO: FASE 1
✅ Permitido: layout.tsx · TopNavigationBar · lib/env.ts · hooks/useAuthToken.ts
⛔ BLOQUEADO: dashboards · rutas secundarias · charts · WebSocket client · auth forms
Si se solicita algo fuera de Fase 1 → RECHAZAR con mensaje:
"⛔ Phase Lock: Esta feature es Fase [X]. Lock actual: Fase 1."
TYPESCRIPT — MODO ESTRICTO
// tsconfig.json — obligatorio
{
"compilerOptions": {
"strict": true,
"noImplicitAny": true,
"strictNullChecks": true,
"noUncheckedIndexedAccess": true
}
}
// ❌ PROHIBIDO — any
const handler = (event: any) => {}
const response: any = await fetch(url)
// ✅ CORRECTO — tipos específicos
const handler = (event: React.MouseEvent<HTMLButtonElement>) => {}
interface ApiResponse<T> { data: T; status: number }
COMPONENTES — REGLAS PRINCIPALES
// ✅ Server Component por defecto (sin directiva)
export function TradingPanel() {
return <div>...</div>
}
// Solo agregar 'use client' si el componente usa:
// - useState, useEffect, useCallback
// - Eventos de browser (onClick, onChange directo)
// - APIs de browser (localStorage, etc.)
"use client";
export function LivePrice() {
const [price, setPrice] = useState(0)
// ...
}
// Máximo 100 líneas por componente.
// Si supera → extraer subcomponentes o un hook.
// ✅ Props tipadas con interface — nunca any
interface TopNavigationBarProps {
items: NavigationItem[]
}
export function TopNavigationBar({ items }: TopNavigationBarProps) {
return (...)
}
DISEÑO — DARK MODE OBLIGATORIO
// ❌ PROHIBIDO — referencia a light mode
className="dark:bg-gray-900 bg-white"
// ❌ PROHIBIDO — colores hardcodeados
style={{ color: "#f0f0f5" }}
// ✅ CORRECTO — CSS variables del design system
className="bg-bg-surface text-text-primary border-border-subtle"
// El Top Nav usa glassmorphism exacto:
const navClasses = [
"fixed top-0 left-0 right-0 z-50 h-14",
"flex items-center justify-between px-6",
"bg-[rgba(17,17,24,0.72)] backdrop-blur-md",
"border-b border-border-subtle",
].join(" ")
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.
- 1mo ago First seen · 189 lines · 0 tokens per session scan A 9f9bb1650310
03-frontend-nextjs is a cursor rule published in the GitHub repository juandoroteoflesiauni-lang/Market-options-stocks-Scanner (12 stars, last pushed 4mo ago), licensed Apache-2.0. It costs nothing until one of its globs matches a file; then it loads 1,391 tokens. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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