C# Clean Code Skill

An AI agent skill that enforces C# clean code conventions across any .NET project.

Overview

This skill provides a comprehensive C# style guide with 12 mandatory rules (blockers) and 18 recommended rules (strongly encouraged). When loaded by an AI coding agent, it guides code review, refactoring, and generation to follow consistent, readable C# patterns.

Structure

.agents/skills/csharp-clean-code/
  SKILL.md    # Full style guide with rules, examples, and quick-review checklist

Highlights

Mandatory rules include:

• File-scoped namespaces
• English for all user-facing messages
• PascalCase/camelCase/_camelCase naming conventions
• Language keywords over CLR types (string not String)
• Braces on all control flow; switch must have default
• Explicit Main method (no top-level statements)
• No magic numbers; one type per file
• Exceptions only for exceptional conditions, with nameof(param)

Recommended rules include:

• using declarations, expression-bodied members, pattern matching
• Null-conditional operators, string interpolation, collection expressions
• nameof(), records for immutable data, proper async/await
• Comment "why" not "what", avoid double negatives and nested loops
• Declare variables late, one per statement, avoid ref/out

Usage

This skill works with any AI coding agent (OpenCode, Claude, Cursor, etc.). Once installed, the agent applies these rules automatically when writing, reviewing, or refactoring C# code.