CSharpGuidelines plugin
The csharp-guidelines plugin checks agent-written .NET code against Dennis Doomen's AV0100–AV2400 rules, up to language v14.
- 784 ★ on the repository
- Last commit
Minimal access
Why this level
- Adds reference rules for the agent and changes no project files itself.
Install
- Works in
In your terminal, with SkillFoxx CLI
npx skillfoxx add plugins/csharpguidelinesDetects the agents on your machine, shows the access level and pins the version.
Other ways to install
Access and checks
How we reviewMinimal accessThe tool runs nothing and makes no network calls.
- Adds reference rules for the agent and changes no project files itself.
This is third-party code. Review the repository files before installing.
What it does
Besides the site and PDFs, the C# Coding Guidelines repository serves as a plugin marketplace for Claude Code and GitHub Copilot CLI. The `csharp-guidelines` skill makes the agent apply the rules when writing, reviewing and refactoring C#. The rules are spread across eleven reference files: general principles, class design, member design, miscellaneous design, maintainability, testability, naming, performance, framework usage, documentation and layout. Each rule has a number and a level: must, should or may.
Who it is for. .NET developers and teams that keep one C# style and want the agent to write and review code by the same rules as people.
Good fit when
- The agent generates a class that must be checked against the rules on coupling and responsibility.
- A C# pull request is under review and the criteria live in a shared reference.
- Refactoring a method with a long parameter list and nested branches.
- A team needs one scheme for naming and member order.
Not a fit when
- The project is not C#: the rules are tied to the language.
- An automatic analyzer in the build is needed: the skill guides the agent but is not an analyzer.
- The team already has its own style that diverges from the rules.
Example request
Review this C# file against csharp-guidelines, name the violated rules with AV numbers and propose fixes.Limitations
The skill steers the agent but does not verify the build: it blocks no violations, and analyzers are needed for that. The references cover C# up to version 14. The agent interprets the must, should and may levels itself, so disputed places deserve a human look. The plugin installs through the Claude Code or Copilot CLI marketplace, and for other agents `SKILL.md` must be wired in by hand. Rights in the rule text are stated in the repository's `LICENSE.md`.
How to disable. Remove the `csharp-guidelines` plugin with your agent's plugin command and drop the marketplace from the list. The plugin changed no project files.
FAQ
How do I install it in Claude Code?
Run `claude plugin install csharp-guidelines --marketplace dennisdoomen/CSharpGuidelines`.
How do I install it in Copilot CLI?
Run `copilot plugin marketplace add dennisdoomen/CSharpGuidelines`, then `copilot plugin install csharp-guidelines@csharp-guidelines`.
What do rule levels mean?
Must is always enforced, Should is followed unless there is a clear reason not to, and May is optional good practice.
How do I build the PDFs?
Run `build.ps1` on Windows or `./build.sh` on macOS and Linux. The .NET 10 SDK and Google Chrome are required.
What is the license?
The repository contains `LICENSE.md`. See it for the terms of use of the rule text.
Discussion
No questions or reviews yet.
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Comparison with similar tools
Cards that share the main search query, and how they differ.
| Tool | Official | Repository stars | Main difference |
|---|---|---|---|
| CSharpGuidelines (this card) | no | 784 | |
| dotnet-skills: a skill installer for .NET | no | 513 | a general .NET skill set; csharp-guidelines reduces code rules to one numbered AV reference |
| dotnet-artisan | no | 237 | a broad .NET development set; csharp-guidelines focuses on C# code style and design |
README in short
The README points to the rules site, gives skill install commands for Claude Code and Copilot CLI, and covers building the PDFs and previewing the site locally with Jekyll.