Copilot-Skills: Instructions file for GitHub Copilot

.github/instructions/typescript.instructions.md

Copilot-Skills typescript.instructions.md is an instructions file for GitHub Copilot from TheSethRose/Copilot-Skills. It costs 286 tokens per session, scanned A, original, MIT.

A set of coding instructions for TypeScript, a version of JavaScript that adds type checking. It covers setup, naming, error handling, documentation, and commonly recommended patterns.

In plain words
What is it for?
Use it when creating or editing TypeScript, TSX, or TypeScript configuration files.
Why use it?
It helps the coding agent write more consistent TypeScript and catch type-related mistakes earlier. It also discourages deprecated approaches.

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/typescript.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 typescript.instructions.md

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

Your own site · 80×15
<a href="https://agentmods.dev/instructions/thesethrose/copilot-skills/typescript"><img src="https://agentmods.dev/badge/instructions/thesethrose/copilot-skills/typescript.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 286 This file is loaded in full into every session.
When invoked 286 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 $0.00286 $0.00286
Opus 5.5 $0.00114 $0.00114
Sonnet 5.5 $0.00057 $0.00057
Haiku 4.5 $0.00029 $0.00029

Measured 1mo ago against content hash 63dbe982af10, 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 typescript.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/typescript.instructions.md · 48 lines

What it actually says

Typescript Instructions

Auto-loaded when: Working with files matching: **/*.ts, **/*.tsx, **/tsconfig.json

Default Behaviors

When working with typescript:

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

Debugging

Common issues and solutions documented in references/ files.

Quality Guidelines

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

Resources

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 · 286 tokens per session scan A 63dbe982af10

Subscribe to this mod's changes

Copilot-Skills typescript.instructions.md is an instructions file published in the GitHub repository TheSethRose/Copilot-Skills (3 stars, last pushed 10mo ago), licensed MIT. It adds 286 tokens to every session, about $0.0011 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 2026-09-03.

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