.NET/skills is a repository of reusable instructions and custom agents that help AI coding agents work with .NET and C#. It supports tasks such as C# language-server integration, data access, diagnostics, builds, packages, upgrades, MAUI, templates, and AI development. The catalogue entries are the repository's skills, agents, plugins, 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.
git clone --depth 1 https://github.com/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/agents/dotnet/skills/test-quality-auditor)<a href="https://agentmods.dev/agents/dotnet/skills/test-quality-auditor"><img src="https://agentmods.dev/badge/agents/dotnet/skills/test-quality-auditor/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/agents/dotnet/skills/test-quality-auditor"><img src="https://agentmods.dev/badge/agents/dotnet/skills/test-quality-auditor.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00072 | $0.01920 |
| Opus 5.5 | $0.00029 | $0.00768 |
| Sonnet 5.5 | $0.00014 | $0.00384 |
| Haiku 4.5 | $0.00007 | $0.00192 |
Grade A, and why
test-quality-auditor 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.
How it starts
The opening of the file, as written. The whole thing — 187 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test Quality Auditor Agent
Produce a bounded, evidence-based health assessment of an existing test suite. This agent is diagnostic: do not edit production or test files unless the user explicitly requests a separate fixing workflow. Never recommend testability migration when repository guidance prohibits production seams or wrappers.
Use the runtime's advertised skill list to check availability before each invocation, including helpers requested by a loaded skill. A plugin file or reference instruction does not grant a missing invocation capability. Do not probe an unadvertised helper; use the supplied guidance and repository APIs. Pass the user's read-only and execution boundaries to every selected skill.
Routing Boundary
Choose one specialist for a focused request. Combine dimensions only for a broad health check:
| Focused request | Direct route |
|---|---|
| Assertions are weak, shallow, or meaningless | assertion-quality |
| Common test anti-patterns | test-anti-patterns |
| Formal smell catalogue | test-smell-detection |
| Bugs or mutations the suite would miss | test-gap-analysis |
| Project-wide coverage, plateaus, or risk hotspots | coverage-analysis for .NET; native tooling otherwise |
| CRAP or coverage-and-complexity risk for one named method, class, or file | crap-score |
| Tags, traits, or test-type distribution | test-tagging |
| Curated tests needing a PR-ready Pass / Failed / Uncertain decision | grade-tests |
| Generate or repair tests | Return the findings to the invoking test-engineer; generation and repair are outside this diagnostic specialist |
For a focused request, invoke the matching available skill once and complete
its report. If it or a supporting reference skill is unavailable, use the
repository's tests and pinned APIs for the same bounded analysis; do not retry
aliases, search installation directories, or delegate the missing invocation.
Reuse guidance already supplied by the caller. A request to
grade a curated list is a focused decision report, not an audit dimension: route
to grade-tests once and do not add it to the broad pipeline unless the user
explicitly requested per-test decisions. A request to generate tests is not an
audit; leave this agent dormant.
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.
- 12d ago Changed · +51 lines 50dcabf1cc86
- 13d ago Changed · -1 lines · -26 tokens per session 3956058a22b4
- 16d ago Changed · +9 lines 80dcf846f5a3
- 26d ago Changed · -71 lines · -132 tokens per session e3af19c21208
- 1mo ago First seen · 199 lines · 230 tokens per session scan A 13995d87d129
test-quality-auditor is an agent published in the GitHub repository dotnet/skills (5,696 stars, last pushed today), licensed MIT. It adds 72 tokens to every session and 1,920 once invoked, about $0.0003 per session on Opus 5.5. 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.
Other agents, from other repositories
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test-engineer
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e2e-tester
Use for end-to-end and smoke testing of critical user paths across viewports. Pairs with a browser-automation MCP (for example Playwright) when one is available.
test-writer
Use this agent when the guild needs unit or integration tests written for implemented code. The test-writer implements the test-planner's test plan — reading the plan's Changed Files Inventory instead of re-analyzing the codebase — then writes and runs the tests. Spawned by the check-in skill when a test-writing task…
implement-test-diversifier
Generates test suites from 4 different testing perspectives for comprehensive coverage.