rugged-gemini: Skill for Claude Code

.gemini/skills/dotnet-idioms/SKILL.md

dotnet-idioms is a skill for Claude Code, Gemini CLI from irahardianto/rugged-gemini. It costs 0 tokens per session (616 once invoked), scanned A, original, MIT.

A reference for idiomatic .NET 8 and later application design, covering patterns such as minimal APIs, dependency injection, asynchronous code, and Entity Framework Core.

In plain words
What is it for?
Use it when designing .NET endpoints, configuring services, querying databases, managing migrations, and organizing application configuration.
Why use it?
It helps developers choose current .NET patterns and avoid designs that are unnecessarily complex or poorly suited to modern cloud applications.

Skill for Claude CodeGemini CLI

Written for Claude Code and Gemini CLI: paths in frontmatter, but also installed under .gemini/.

This is irahardianto/rugged-gemini's own configuration. It tells Claude Code and Gemini CLI how to work on rugged-gemini 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 rugged-gemini configures →

Reuse

Borrowing it

Nothing to install: this file belongs to irahardianto/rugged-gemini. 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/irahardianto/rugged-gemini/main/.gemini/skills/dotnet-idioms/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/irahardianto/rugged-gemini

Made for: Claude Code, Gemini CLI.

Wrote this? Show the measurements

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README.md
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Your own site · 80×15
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Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 616 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
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 $0.00000 $0.00616
Opus 5 $0.00000 $0.00308
Sonnet 5 $0.00000 $0.00123
Haiku 4.5 $0.00000 $0.00062

Measured 12d ago against content hash d5b159bb69e4, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

dotnet-idioms 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 12d 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.

.gemini/skills/dotnet-idioms/SKILL.md · 85 lines

How it starts

The opening of the file, as written. The whole thing — 85 lines — stays where its author put it; the contents beside it link to each section on GitHub.

.NET Idioms and Patterns

.NET 8+ rewards minimal APIs, DI, and async-first design. Idiomatic .NET = clean, performant, cloud-native.

Scope: .NET framework patterns. For C#: @.gemini/skills/csharp-idioms/SKILL.md.

Minimal APIs

  1. Minimal APIs for simple endpoints:

    app.MapGet("/api/tasks/{id}", async (string id, ITaskService service) =>
        await service.GetByIdAsync(id) is Task task
            ? Results.Ok(task)
            : Results.NotFound());
    
    app.MapPost("/api/tasks", async (CreateTaskRequest request, ITaskService service) =>
    {
        var task = await service.CreateAsync(request);
        return Results.Created($"/api/tasks/{task.Id}", task);
    });
    
  2. Controllers for complex endpoints with filters, model binding, etc.

Entity Framework Core

  1. DbContext per request (scoped lifetime).
  2. Migrations via CLI:
    dotnet ef migrations add AddTaskPriority
    dotnet ef database update
    
  3. AsNoTracking() for read-only queries.
  4. Compiled queries for hot paths.

Configuration

  1. IOptions<T> pattern for strongly-typed config:

    builder.Services.Configure<DatabaseOptions>(builder.Configuration.GetSection("Database"));
    
  2. User secrets for local development, Key Vault for production.

Middleware

  1. Custom middleware for cross-cutting concerns (logging, correlation IDs).
  2. UseExceptionHandler for global error handling.

Testing

  1. xUnit + FluentAssertions:

    [Fact]
    public async Task GetTask_ReturnsOk_WhenExists()
    {
        var client = _factory.CreateClient();
        var response = await client.GetAsync("/api/tasks/1");
        response.StatusCode.Should().Be(HttpStatusCode.OK);
    }
    
  2. WebApplicationFactory<T> for integration tests.

  3. Respawn for database cleanup.

Formatting and Static Analysis

Tool Purpose Command
dotnet format Formatting dotnet format
Roslyn analyzers Analysis Built-in
dotnet list package --vulnerable CVE scanning Built-in

Read the full file on GitHub · 85 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. 12d ago First seen · 85 lines · 0 tokens per session scan A d5b159bb69e4

Subscribe to this mod's changes

dotnet-idioms is a skill published in the GitHub repository irahardianto/rugged-gemini (5 stars, last pushed 4mo ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 616 tokens. 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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