Copilot-Skills: Instructions file for GitHub Copilot

.github/instructions/headless-ui.instructions.md

Copilot-Skills headless-ui.instructions.md is an instructions file for GitHub Copilot from TheSethRose/Copilot-Skills. It costs 293 tokens per session, scanned A, original, MIT.

Coding guidance for Headless UI, a library of interface components without built-in visual styling. It applies to React and Vue component files.

In plain words
What is it for?
It is for building, reviewing, testing, and maintaining Headless UI components in .tsx, .jsx, and .vue files.
Why use it?
It helps developers follow the library’s documented patterns and avoid deprecated or unsafe usage. It also points to setup and debugging references.

Instructions file for GitHub Copilot

Written for GitHub Copilot: a Copilot instructions file.

This is TheSethRose/Copilot-Skills's own configuration. It tells GitHub Copilot how to work on Copilot-Skills 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 Copilot-Skills configures →

Reuse

Borrowing it

Nothing to install: this file belongs to TheSethRose/Copilot-Skills. 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/TheSethRose/Copilot-Skills/main/.github/instructions/headless-ui.instructions.md
Clone the repo
git clone --depth 1 https://github.com/TheSethRose/Copilot-Skills

Made for: GitHub Copilot.

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 Copilot-Skills headless-ui.instructions.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/thesethrose/copilot-skills/headless-ui/github.svg)](https://agentmods.dev/instructions/thesethrose/copilot-skills/headless-ui)
Your own site
<a href="https://agentmods.dev/instructions/thesethrose/copilot-skills/headless-ui"><img src="https://agentmods.dev/badge/instructions/thesethrose/copilot-skills/headless-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 Copilot-Skills headless-ui.instructions.md

Your own site · 80×15
<a href="https://agentmods.dev/instructions/thesethrose/copilot-skills/headless-ui"><img src="https://agentmods.dev/badge/instructions/thesethrose/copilot-skills/headless-ui.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 293 This file is loaded in full into every session.
When invoked 293 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 $0.00293 $0.00293
Opus 5.5 $0.00117 $0.00117
Sonnet 5.5 $0.00059 $0.00059
Haiku 4.5 $0.00029 $0.00029

Measured 1mo ago against content hash 60848524aa2d, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

Copilot-Skills headless-ui.instructions.md 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 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.

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.

.github/instructions/headless-ui.instructions.md · 48 lines

What it actually says

Headless-Ui Instructions

Auto-loaded when: Working with files matching: **/*.tsx, **/*.jsx, **/*.vue

Default Behaviors

When working with headless-ui:

  1. Follow Official Patterns: Use patterns from official headless-ui documentation
  2. Code Quality: Follow headless-ui best practices and conventions
  3. Error Handling: Implement robust error handling appropriate for headless-ui
  4. Documentation: Include inline comments for complex headless-ui usage

Common Workflows

Setup & Installation

Check references/getting_started.md for:

  • Installation steps
  • Configuration options
  • Initial setup

Development

  1. Reference official documentation patterns
  2. Use type-safe code when applicable
  3. Follow headless-ui naming conventions
  4. Test thoroughly

Debugging

Common issues and solutions documented in references/ files.

Quality Guidelines

  • ✅ Use official headless-ui APIs and patterns
  • ✅ Follow community best practices
  • ✅ Write maintainable, readable code
  • ✅ Include error handling
  • ⚠️ Avoid deprecated features
  • ⚠️ Don't bypass headless-ui safety features

Resources

  • Skill prompt: .github/prompts/headless-ui.skill.prompt.md
  • References: .github/copilot-skills/frontend/headless-ui/references/
  • Official docs: https://headlessui.com/
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. 1mo ago First seen · 48 lines · 293 tokens per session scan A 60848524aa2d

Subscribe to this mod's changes

Copilot-Skills headless-ui.instructions.md is an instructions file published in the GitHub repository TheSethRose/Copilot-Skills (3 stars, last pushed 10mo ago), licensed MIT. It adds 293 tokens to every session, about $0.0012 per session on Opus 5.5. 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 2026-08-31.

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