pn-vanilla-web

pn-vanilla-web is a cursor rule for Cursor from perniemann/pnCore. It costs 216 tokens per session, scanned A, original, MIT.

A set of conventions for plain HTML, CSS, and JavaScript websites. It covers meaningful HTML structure, accessibility, responsive layouts, progressive enhancement, and keeping JavaScript small.

In plain words
What is it for?
Use it when editing HTML files or building a website without a frontend framework.
Why use it?
It reduces common usability and maintenance problems, such as missing form labels, poor keyboard navigation, tiny touch targets, and layouts that depend entirely on JavaScript.

Cursor rule for Cursor

Written for Cursor: a Cursor rule (.mdc).

Good fit Use it when editing HTML files or building a website without a frontend framework.

Compare 6 cursor rules from other repositories ↓
Install with agentmods
npx agentmods add rules/perniemann/pncore/pn-vanilla-web
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/perniemann/pnCore

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 pn-vanilla-web

README.md
[![agentmods](https://agentmods.dev/badge/rules/perniemann/pncore/pn-vanilla-web.svg)](https://agentmods.dev/rules/perniemann/pncore/pn-vanilla-web)
Your own site
<a href="https://agentmods.dev/rules/perniemann/pncore/pn-vanilla-web"><img src="https://agentmods.dev/badge/rules/perniemann/pncore/pn-vanilla-web.svg" alt="Measured on agentmods" height="20"></a>
Per session 216 This file is loaded in full into every session.
When invoked 216 The same file — it is already loaded in full.
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 $0.00216 $0.00216
Opus 5 $0.00108 $0.00108
Sonnet 5 $0.00043 $0.00043
Haiku 4.5 $0.00022 $0.00022

Measured 3d ago against content hash e743869b654a, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

pn-vanilla-web 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 3d 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.

packages/pn-core-mcp/content/rules/pn-vanilla-web.mdc · 16 lines

What it actually says

Vanilla web rules

  • Use semantic HTML: <header>, <main>, <nav>, <footer>, <article>, <section>, <aside>.
  • Prefer progressive enhancement: content works without JavaScript; JS adds interactivity.
  • Use consistent class naming: BEM or kebab-case. Avoid inline styles for layout; use CSS classes.
  • CSS variables for theming (colors, spacing, typography); reference pn-design-system for token structure.
  • A11y: one <h1> per page, labels for form controls, logical heading order, focus order.
  • Responsive and touch: mobile-first; min 44×48px touch targets; no hover-only for critical actions; never disable zoom.
  • Keep JS minimal; no unnecessary libraries unless required by the feature.
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. 3d ago First seen · 16 lines · 216 tokens per session scan A e743869b654a

Subscribe to this mod's changes

pn-vanilla-web is a cursor rule published in the GitHub repository perniemann/pnCore (0 stars, last pushed today), licensed MIT. It adds 216 tokens to every session, about $0.0011 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 2026-09-03.