teak: Skill for Claude Code

.agents/skills/ultracite/SKILL.md

ultracite is a skill for Claude Code, Codex from praveenjuge/teak. It costs 142 tokens per session (1,256 once invoked), scanned A, a copy of ultracite, MIT.

A ready-made linting and formatting setup for JavaScript and TypeScript projects. Linting finds likely code problems, while formatting applies consistent code style.

In plain words
What is it for?
Initializing a project setup, checking or fixing files, diagnosing configuration, and using Biome, ESLint with Prettier, or Oxlint with Oxfmt.
Why use it?
It removes the need to design and maintain these rules from scratch. It can also diagnose setup issues and automatically fix supported problems.

Skill for Claude CodeCodex

Which agent this was written for is unclear — built for cline. Also seen: installed under .agents/ (shared by several agents); mentions Codex; built for cline.

This is praveenjuge/teak's own configuration. It tells Claude Code and Codex how to work on teak itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything teak configures →

Reuse

Borrowing it

Nothing to install: this file belongs to praveenjuge/teak. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/praveenjuge/teak/main/.agents/skills/ultracite/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/praveenjuge/teak

Made for: Claude Code, Codex.

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 ultracite

README.md
[![agentmods](https://agentmods.dev/badge/skills/praveenjuge/teak/ultracite/github.svg)](https://agentmods.dev/skills/praveenjuge/teak/ultracite)
Your own site
<a href="https://agentmods.dev/skills/praveenjuge/teak/ultracite"><img src="https://agentmods.dev/badge/skills/praveenjuge/teak/ultracite/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 ultracite

Your own site · 80×15
<a href="https://agentmods.dev/skills/praveenjuge/teak/ultracite"><img src="https://agentmods.dev/badge/skills/praveenjuge/teak/ultracite.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 142 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,256 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 88% 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 5.1 $0.00142 $0.01256
Opus 5.5 $0.00057 $0.00502
Sonnet 5.5 $0.00028 $0.00251
Haiku 4.5 $0.00014 $0.00126

Measured 2mo ago against content hash 84da9f8f211a, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, 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 2mo 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

88% identical to ultracite — 22 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.

.agents/skills/ultracite/SKILL.md · 103 lines

How it starts

The opening of the file, as written. The whole thing — 103 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Ultracite

Zero-config linting and formatting for JS/TS projects. Supports three linter backends: Biome (recommended), ESLint + Prettier, and Oxlint + Oxfmt.

Detecting Ultracite

Check if ultracite is in package.json devDependencies. Detect the active linter by looking for:

  • biome.jsonc → Biome
  • eslint.config.mjs → ESLint
  • .oxlintrc.json → Oxlint

CLI Commands

# Check for issues (read-only)
bunx ultracite check

# Auto-fix issues
bunx ultracite fix

# Diagnose setup problems
bunx ultracite doctor

# Initialize in a new project
bunx ultracite init

Replace bunx with npx, pnpx, or yarn dlx depending on the package manager.

check and fix accept optional file paths: bunx ultracite check src/index.ts.

Initialization

bunx ultracite init runs an interactive setup. For non-interactive (CI) use, pass flags:

bunx ultracite init \
  --pm bun \
  --linter biome \
  --editors vscode cursor \
  --agents claude copilot \
  --frameworks react next \
  --integrations husky lint-staged \
  --quiet

Flags:

  • --pm — npm | yarn | pnpm | bun
  • --linter — biome (recommended) | eslint | oxlint
  • --editors — vscode | zed | cursor | windsurf | antigravity | kiro | trae | void
  • --agents — claude | codex | copilot | cline | amp | gemini | cursor-cli + 19 more
  • --frameworks — react | next | solid | vue | svelte | qwik | remix | angular | astro | nestjs
  • --integrations — husky | lefthook | lint-staged | pre-commit
  • --hooks — Enable auto-fix hooks for supported agents/editors
  • --type-aware — Enable type-aware linting (oxlint only)
  • --skip-install — Skip dependency installation
  • --quiet — Suppress prompts (auto-detected when CI=true)

Init creates config that extends Ultracite presets:

// biome.jsonc
{ "extends": ["ultracite/biome/core", "ultracite/biome/react"] }

Framework presets available per linter: core, react, next, solid, vue, svelte, qwik, remix, angular, astro, nestjs.

Read the full file on GitHub · 103 lines

Files

What ships with it

1 file 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. 2mo ago First seen · 103 lines · 142 tokens per session scan A 84da9f8f211a

Subscribe to this mod's changes

ultracite is a skill published in the GitHub repository praveenjuge/teak (24 stars, last pushed yesterday), licensed MIT. It adds 142 tokens to every session and 1,256 once invoked, about $0.0006 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 88% identical to ultracite, differing in 22 lines, and is treated as a copy.

Related

ultracite compared with skills from other repositories

ultracite next to 6 skills from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
ultracitepraveenjuge/teakSkill24yesterdayMITA142Claude Code, Codex
javascript-sandboxmereyabdenbekuly-ctrl/clodex-ideSkill87014d agoAGPL-3.0A38Claude Code, Codex
cli-wiringgithub/gh-awSkill5.6kyesterdayMITA0Claude Code, Codex
configkubb-labs/kubbSkill1.8kyesterdayMITA49Claude Code
extending-personhog-test-harnessPostHog/posthogSkill41kyesterdaynoneA134Claude Code, Codex
agent-inspectrajudandigam/agent-inspectSkill1712d agoMITA52Claude Code, Codex
error-handlingmetarhia/metaskillsSkill607d agoMITA70Claude Code, Codex