microsoft-authentication-library-common-for-objc: Instructions file for GitHub Copilot

.github/copilot-instructions.md

microsoft-authentication-library-common-for-objc copilot-instructions.md is an instructions file for GitHub Copilot from AzureAD/microsoft-authentication-library-common-for-objc. It costs 798 tokens per session, scanned A, original, MIT.

Repository guidance for an Objective-C library used inside Microsoft's authentication software for iOS, macOS, and visionOS. It explains the project structure and how to build and run its tests.

In plain words
What is it for?
Making or reviewing changes in the IdentityCore library, including running the Python build script for each Apple platform and its unit tests.
Why use it?
It gives a coding agent the project's platform details and validation steps, reducing incorrect changes and missed tests.

Instructions file for GitHub Copilot

Written for GitHub Copilot: a Copilot instructions file.

This is AzureAD/microsoft-authentication-library-common-for-objc's own configuration. It tells GitHub Copilot how to work on microsoft-authentication-library-common-for-objc 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 microsoft-authentication-library-common-for-objc configures →

Reuse

Borrowing it

Nothing to install: this file belongs to AzureAD/microsoft-authentication-library-common-for-objc. 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/AzureAD/microsoft-authentication-library-common-for-objc/dev/.github/copilot-instructions.md
Clone the repo
git clone --depth 1 https://github.com/AzureAD/microsoft-authentication-library-common-for-objc

Made for: GitHub Copilot.

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README.md
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<a href="https://agentmods.dev/instructions/azuread/microsoft-authentication-library-common-for-objc/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/azuread/microsoft-authentication-library-common-for-objc/copilot-instructions.svg" alt="Measured on agentmods" height="20"></a>
Per session 798 This file is loaded in full into every session.
When invoked 798 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 $0.00798 $0.00798
Opus 5 $0.00399 $0.00399
Sonnet 5 $0.00160 $0.00160
Haiku 4.5 $0.00080 $0.00080

Measured yesterday against content hash a1e97490a474, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

microsoft-authentication-library-common-for-objc copilot-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 yesterday.

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/copilot-instructions.md · 73 lines

How it starts

The opening of the file, as written. The whole thing — 73 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Copilot Instructions for IdentityCore

This repository contains IdentityCore, a shared library used by the Microsoft Authentication Library (MSAL) for iOS and macOS. It contains internal classes and is not intended for public API consumption.

High Level Details

  • Project Type: Objective-C Shared Library (Internal).
  • Languages: Objective-C, Python (build scripts).
  • Platforms: iOS, macOS, visionOS.
  • Key Frameworks: Foundation, Security.
  • Versioning: Semantic Versioning.
  • Branching: main is the active branch. dev is the active development branch.

Build and Validation

To build and validate changes, use the provided Python build script. This script handles building the project and running unit tests.

Build and Test: Run the build.py script with the appropriate target. This command performs both build and test operations by default.

# For iOS
./build.py --targets ios_library

# For macOS
./build.py --targets mac_library

# For visionOS
./build.py --targets vision_library

Note:

  • The build script uses xcodebuild under the hood.
  • Ensure you have the appropriate Xcode version selected (CI uses Xcode 16.2).
  • The build script requires xcpretty by default. If xcpretty is not installed locally, use --no-xcpretty to bypass it.
  • If you encounter issues, try running with --no-clean to speed up subsequent builds or --show-build-settings for debugging.
  • The iOS simulator device and OS version are hardcoded in build.py (e.g., ios_sim_device and ios_sim_dest). If the configured simulator is not available in your local Xcode/simulator environment, update these variables to match an available device and runtime (use xcrun simctl list devices available to check).

Code Style

CRITICAL: Always adhere to the code style guidelines defined in .clinerules/01-Code-style-guidelines.md. This includes:

  • Using dot notation for properties.
  • 4-space indentation.
  • Opening braces on a NEW line.
  • Using MSID prefix classes.
  • Checking return values instead of error variables.

Read the full file on GitHub · 73 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. yesterday First seen · 73 lines · 798 tokens per session scan A a1e97490a474

Subscribe to this mod's changes

microsoft-authentication-library-common-for-objc copilot-instructions.md is an instructions file published in the GitHub repository AzureAD/microsoft-authentication-library-common-for-objc (65 stars, last pushed yesterday), licensed MIT. It adds 798 tokens to every session, about $0.0040 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 2026-09-04.

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