Copilot-Skills: Instructions file for GitHub Copilot

.github/instructions/better-auth.instructions.md

Copilot-Skills better-auth.instructions.md is an instructions file for GitHub Copilot from TheSethRose/Copilot-Skills. It costs 350 tokens per session, scanned A, original, MIT.

A set of coding instructions for Better Auth, a library for adding authentication features such as user sign-in to web applications.

In plain words
What is it for?
Use it when setting up, developing, documenting, testing, or debugging Better Auth configuration and application code.
Why use it?
It guides implementation toward Better Auth’s documented patterns, error handling, testing, and maintainable code.

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/better-auth.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 better-auth.instructions.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/thesethrose/copilot-skills/better-auth.svg)](https://agentmods.dev/instructions/thesethrose/copilot-skills/better-auth)
Your own site
<a href="https://agentmods.dev/instructions/thesethrose/copilot-skills/better-auth"><img src="https://agentmods.dev/badge/instructions/thesethrose/copilot-skills/better-auth.svg" alt="Measured on agentmods" height="20"></a>
Per session 350 This file is loaded in full into every session.
When invoked 350 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
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 $0.00350 $0.00350
Opus 5 $0.00175 $0.00175
Sonnet 5 $0.00070 $0.00070
Haiku 4.5 $0.00035 $0.00035

Measured 6d ago against content hash 362066346492, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

Copilot-Skills better-auth.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 6d 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

Copies of this mod

8 near-identical copies found in the catalogue:

.github/instructions/better-auth.instructions.md · 56 lines

What it actually says

Better-Auth Instructions

Auto-loaded when: Working with files matching: **/*.ts, **/*.tsx, **/*.js, **/*.jsx, **/auth.config.*

Default Behaviors

When working with better-auth:

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

Debugging

Common issues and solutions documented in references/ files.

Quality Guidelines

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

Resources

  • Skill prompt: .github/prompts/better-auth.skill.prompt.md
  • References: .github/copilot-skills/auth/better-auth/references/
  • Official docs: https://better-auth.com/
  • /nextjs – Next.js authentication setup
  • /sveltekit – SvelteKit integration
  • /fastapi – Python backend integration
  • /prisma – Database schema setup
  • /authjs – Alternative auth solution
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. 6d ago First seen · 56 lines · 350 tokens per session scan A 362066346492

Subscribe to this mod's changes

Copilot-Skills better-auth.instructions.md is an instructions file published in the GitHub repository TheSethRose/Copilot-Skills (3 stars, last pushed 9mo ago), licensed MIT. It adds 350 tokens to every session, about $0.0018 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 2026-08-31.

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