.NET Skills is an AI coding plugin that provides skills and specialized guidance for professional .NET development, covering areas such as C#, Akka.NET, Aspire, Entity Framework Core, testing, and performance. .NET developers use it with coding assistants to apply production-oriented patterns while building and maintaining applications. The catalogue contains the plugin’s skills, agents, and instructions.
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.
npx skills add Aaronontheweb/dotnet-skills --skill slopwatchgit clone --depth 1 https://github.com/Aaronontheweb/dotnet-skillsWrote 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.
[](https://agentmods.dev/skills/aaronontheweb/dotnet-skills/slopwatch)<a href="https://agentmods.dev/skills/aaronontheweb/dotnet-skills/slopwatch"><img src="https://agentmods.dev/badge/skills/aaronontheweb/dotnet-skills/slopwatch/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/aaronontheweb/dotnet-skills/slopwatch"><img src="https://agentmods.dev/badge/skills/aaronontheweb/dotnet-skills/slopwatch.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00047 | $0.02146 |
| Opus 5 | $0.00023 | $0.01073 |
| Sonnet 5 | $0.00009 | $0.00429 |
| Haiku 4.5 | $0.00005 | $0.00215 |
Grade A, and why
dotnet-slopwatch 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 11d 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- dotnet-slopwatch — 100% identical, 1 lines differ
How it starts
The opening of the file, as written. The whole thing — 319 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Slopwatch: LLM Anti-Cheat for .NET
When to Use This Skill
Use this skill constantly. Every time an LLM (including Claude) makes changes to:
- C# source files (.cs)
- Project files (.csproj)
- Props files (Directory.Build.props, Directory.Packages.props)
- Test files
Run slopwatch to validate the changes don't introduce "slop."
What is Slop?
"Slop" refers to shortcuts LLMs take that make tests pass or builds succeed without actually solving the underlying problem. These are reward hacking behaviors - the LLM optimizes for apparent success rather than real fixes.
Common Slop Patterns
| Pattern | Example | Why It's Bad |
|---|---|---|
| Disabled tests | [Fact(Skip="flaky")] |
Hides failures instead of fixing them |
| Warning suppression | #pragma warning disable CS8618 |
Silences compiler without fixing issue |
| Empty catch blocks | catch (Exception) { } |
Swallows errors, hides bugs |
| Arbitrary delays | await Task.Delay(1000); |
Masks race conditions, makes tests slow |
| Project-level suppression | <NoWarn>CS1591</NoWarn> |
Disables warnings project-wide |
| CPM bypass | Version="1.0.0" inline |
Undermines central package management |
Never accept these patterns. If an LLM introduces slop, reject the change and require a proper fix.
Installation
As a Local Tool (Recommended)
Add to .config/dotnet-tools.json:
{
"version": 1,
"isRoot": true,
"tools": {
"slopwatch.cmd": {
"version": "0.2.0",
"commands": ["slopwatch"],
"rollForward": false
}
}
}
Then restore:
dotnet tool restore
As a Global Tool
dotnet tool install --global Slopwatch.Cmd
First-Time Setup: Establish a Baseline
Before using slopwatch on an existing project, create a baseline of current issues:
# Initialize baseline from existing code
slopwatch init
# This creates .slopwatch/baseline.json
git add .slopwatch/baseline.json
git commit -m "Add slopwatch baseline"
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.
- 11d ago First seen · 319 lines · 47 tokens per session scan A eb35bad43b20
dotnet-slopwatch is a skill published in the GitHub repository Aaronontheweb/dotnet-skills (1,150 stars, last pushed today), licensed MIT. It adds 47 tokens to every session and 2,146 once invoked, about $0.0002 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 2026-08-30.
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