awesome-claude-copilot copilot-instructions.md

Repository instructions for GitHub Copilot

Reusable standards for C#/.NET back ends and Angular front ends. This repository contains no application code — it ships GitHub Copilot configuration under .github/: these repository instructions, path-scoped instructions (instructions/), custom agents (agents/), and agent skills (skills/). Follow these instructions for all C# and Angular work.

Communication & comments (always)

Responses

• Lead with the answer or the change. No preamble, no filler, no restating the request.
• Do not re-summarize a plan or diff the user already saw; report only what changed or went wrong.
• Match length to substance — a one-line answer is a complete answer.

Code comments

• Comment only what code cannot say: why a decision was made, constraints, non-obvious invariants, workarounds with links.
• Never narrate what code does. No per-function comment quota. No change-narration comments ("added X", "now uses Y").
• XML doc comments on public APIs are API documentation, not comments — that standard stands.

C# coding standards (always)

Full standards live in instructions/csharp.instructions.md (auto-applies to *.cs). The always-on core:

• Target the latest C# version (currently C# 14); honor .editorconfig; prefer pattern matching, switch expressions, and nameof(...).
• Prefer primary constructors; capture each injected dependency into a private readonly _camelCase field and use the field in method bodies.
• Prefer collection expressions ([], [1, 2, 3], [.. items]) over new List<T>(), new T[] { }, or Array.Empty<T>().
• PascalCase for types, methods, and public members; _camelCase private fields; camelCase locals and parameters; I-prefixed interfaces.
• Declare variables non-nullable; validate null at entry points only; use is null / is not null — never == null / != null.
• Suffix async methods with Async; never block with .Result, .Wait(), or .GetAwaiter().GetResult(); no async void outside event handlers; flow a CancellationToken through long-running operations.
• Centralize error handling; return errors as Problem Details (RFC 9457). Never log PII or secrets; prefer DefaultAzureCredential + Azure Key Vault / Managed Identity over secrets in code or config.
• XML doc comments on all public APIs.
• xUnit tests in a [ProjectName].Tests project, named MethodName_Scenario_ExpectedBehavior; Arrange-Act-Assert structure but no // Arrange / // Act / // Assert comments.
• When reviewing, make only high-confidence suggestions; comment on why a non-obvious design decision was made.