ultracite

A set of formatting and code-checking rules for JavaScript and TypeScript projects, including rules for type safety, accessibility, and consistent style.

In plain words
What is it for?
Use it while writing or checking JavaScript and TypeScript code. It covers HTML accessibility rules and uses Biome for formatting and linting.
Why use it?
It helps catch common code and accessibility problems and keeps files formatted consistently. It also tells an AI coding agent to follow existing project patterns and consider edge cases.

Cursor rule for Cursor

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 rules/doc2mcp/doc2mcp/ultracite
Clone the repo
git clone --depth 1 https://github.com/doc2mcp/doc2mcp

Made for: Cursor.

Per session 3,481 This file is loaded in full into every session.
When invoked 3,481 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod 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 $0.03481 $0.03481
Opus 5 $0.01741 $0.01741
Sonnet 5 $0.00696 $0.00696
Haiku 4.5 $0.00348 $0.00348

Measured 2d ago against content hash f3bdeca1f69a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

ultracite 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 2d 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.

Origin

This is a copy

100% identical to ultracite — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.cursor/rules/ultracite.mdc · 333 lines

How it starts

The opening of the file, as written. The whole thing — 333 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Project Context

Ultracite enforces strict type safety, accessibility standards, and consistent code quality for JavaScript/TypeScript projects using Biome's lightning-fast formatter and linter.

Key Principles

  • Zero configuration required
  • Subsecond performance
  • Maximum type safety
  • AI-friendly code generation

Before Writing Code

  1. Analyze existing patterns in the codebase
  2. Consider edge cases and error scenarios
  3. Follow the rules below strictly
  4. Validate accessibility requirements

Rules

Accessibility (a11y)

  • Don't use accessKey attribute on any HTML element.
  • Don't set aria-hidden="true" on focusable elements.
  • Don't add ARIA roles, states, and properties to elements that don't support them.
  • Don't use distracting elements like <marquee> or <blink>.
  • Only use the scope prop on <th> elements.
  • Don't assign non-interactive ARIA roles to interactive HTML elements.
  • Make sure label elements have text content and are associated with an input.
  • Don't assign interactive ARIA roles to non-interactive HTML elements.
  • Don't assign tabIndex to non-interactive HTML elements.
  • Don't use positive integers for tabIndex property.
  • Don't include "image", "picture", or "photo" in img alt prop.
  • Don't use explicit role property that's the same as the implicit/default role.
  • Make static elements with click handlers use a valid role attribute.
  • Always include a title element for SVG elements.
  • Give all elements requiring alt text meaningful information for screen readers.
  • Make sure anchors have content that's accessible to screen readers.
  • Assign tabIndex to non-interactive HTML elements with aria-activedescendant.
  • Include all required ARIA attributes for elements with ARIA roles.
  • Make sure ARIA properties are valid for the element's supported roles.
  • Always include a type attribute for button elements.
  • Make elements with interactive roles and handlers focusable.
  • Give heading elements content that's accessible to screen readers (not hidden with aria-hidden).
  • Always include a lang attribute on the html element.
  • Always include a title attribute for iframe elements.
  • Accompany onClick with at least one of: onKeyUp, onKeyDown, or onKeyPress.
  • Accompany onMouseOver/onMouseOut with onFocus/onBlur.
  • Include caption tracks for audio and video elements.
  • Use semantic elements instead of role attributes in JSX.
  • Make sure all anchors are valid and navigable.
  • Ensure all ARIA properties (aria-*) are valid.
  • Use valid, non-abstract ARIA roles for elements with ARIA roles.
  • Use valid ARIA state and property values.
  • Use valid values for the autocomplete attribute on input elements.
  • Use correct ISO language/country codes for the lang attribute.

Read the full file on GitHub · 333 lines

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. 2d ago First seen · 333 lines · 3,481 tokens per session scan A f3bdeca1f69a

Subscribe to this mod's changes

ultracite is a cursor rule published in the GitHub repository doc2mcp/doc2mcp (5 stars, last pushed 1mo ago), licensed MIT. It adds 3,481 tokens to every session, about $0.0174 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to ultracite, differing in 0 lines, and is treated as a copy.