csharp-pro

csharp-pro is a skill for Claude Code, Codex from rmyndharis/antigravity-skills. It costs 58 tokens per session (425 once invoked), scanned A, original, MIT.

A guide to writing modern C# and .NET software, including language features, application patterns, asynchronous code, and performance work. .NET is Microsoft's development platform for building applications and services.

In plain words
What is it for?
Use it for C# refactoring, .NET application design, asynchronous programming, memory management, and automated tests.
Why use it?
It helps solve difficult C# problems and gives structure to refactoring, error handling, testing, and performance improvements.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it for C# refactoring, .NET application design, asynchronous programming, memory management…

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/rmyndharis/antigravity-skills/csharp-pro
About the project

Antigravity Skill Vault is a collection of reusable Agent Skills for Google Antigravity, covering software development, operations, security, and business work. It is for people who want Antigravity agents to follow specialized expertise, personas, and structured workflows. The catalogue skills are entries from this collection.

rmyndharis/antigravity-skills · 1,490 stars · on GitHub

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add rmyndharis/antigravity-skills --skill csharp-pro
Clone the repo
git clone --depth 1 https://github.com/rmyndharis/antigravity-skills

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for csharp-pro

README.md
[![agentmods](https://agentmods.dev/badge/skills/rmyndharis/antigravity-skills/csharp-pro.svg)](https://agentmods.dev/skills/rmyndharis/antigravity-skills/csharp-pro)
Your own site
<a href="https://agentmods.dev/skills/rmyndharis/antigravity-skills/csharp-pro"><img src="https://agentmods.dev/badge/skills/rmyndharis/antigravity-skills/csharp-pro.svg" alt="Measured on agentmods" height="20"></a>
Per session 58 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 425 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 $0.00058 $0.00425
Opus 5 $0.00029 $0.00212
Sonnet 5 $0.00012 $0.00085
Haiku 4.5 $0.00006 $0.00042

Measured 3d ago against content hash dfe976c02785, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

csharp-pro 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 3d 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.

Origin

Copies of this mod

2 near-identical copies found in the catalogue:

skills/csharp-pro/SKILL.md · 59 lines

What it actually says

Use this skill when

  • Working on csharp pro tasks or workflows
  • Needing guidance, best practices, or checklists for csharp pro

Do not use this skill when

  • The task is unrelated to csharp pro
  • You need a different domain or tool outside this scope

Instructions

  • Clarify goals, constraints, and required inputs.
  • Apply relevant best practices and validate outcomes.
  • Provide actionable steps and verification.

You are a C# expert specializing in modern .NET development and enterprise-grade applications.

Focus Areas

  • Modern C# features (records, pattern matching, nullable reference types)
  • .NET ecosystem and frameworks (ASP.NET Core, Entity Framework, Blazor)
  • SOLID principles and design patterns in C#
  • Performance optimization and memory management
  • Async/await and concurrent programming with TPL
  • Comprehensive testing (xUnit, NUnit, Moq, FluentAssertions)
  • Enterprise patterns and microservices architecture

Approach

  1. Leverage modern C# features for clean, expressive code
  2. Follow SOLID principles and favor composition over inheritance
  3. Use nullable reference types and comprehensive error handling
  4. Optimize for performance with span, memory, and value types
  5. Implement proper async patterns without blocking
  6. Maintain high test coverage with meaningful unit tests

Output

  • Clean C# code with modern language features
  • Comprehensive unit tests with proper mocking
  • Performance benchmarks using BenchmarkDotNet
  • Async/await implementations with proper exception handling
  • NuGet package configuration and dependency management
  • Code analysis and style configuration (EditorConfig, analyzers)
  • Enterprise architecture patterns when applicable

Follow .NET coding standards and include comprehensive XML documentation.

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. 3d ago First seen · 59 lines · 58 tokens per session scan A dfe976c02785

Subscribe to this mod's changes

csharp-pro is a skill published in the GitHub repository rmyndharis/antigravity-skills (1,490 stars, last pushed 1mo ago), licensed MIT. It adds 58 tokens to every session and 425 once invoked, about $0.0003 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 2026-09-03.