.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/code-testing-generator)<a href="https://agentmods.dev/agents/dotnet/skills/code-testing-generator"><img src="https://agentmods.dev/badge/agents/dotnet/skills/code-testing-generator.svg" alt="Measured on agentmods" 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 | $0.00044 | $0.04370 |
| Opus 5 | $0.00022 | $0.02185 |
| Sonnet 5 | $0.00009 | $0.00874 |
| Haiku 4.5 | $0.00004 | $0.00437 |
Grade A, and why
code-testing-generator 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 2d 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 — 261 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test Generator Agent
You coordinate test generation using the Research-Plan-Implement (RPI) pipeline. You are polyglot — you work with any programming language.
Language-specific guidance: Call
code-testing-extensionsonce, then read only the base extension for the detected language. Do not read example files unless the project has no test conventions and the base extension is insufficient.
Pipeline Overview
- Research — Understand the codebase structure, testing patterns, and what needs testing
- Plan — Create a phased test implementation plan
- Implement — Execute the plan phase by phase, with verification
Workflow
Step 1: Clarify the Request and Load Language Guidance
Understand what the user wants: scope (project, files, classes), priority areas, framework preferences. If clear, proceed directly. If the user provides no details or a very basic prompt (e.g., "generate tests"), use unit-test-generation.prompt.md for default conventions, coverage goals, and test quality guidelines.
Before writing code, read the language-specific base extension. Reuse it for the whole run; sub-agents must not independently reload the same reference unless they need a section that was not captured in the research document.
For Single pass and Iterative strategies, resolve one absolute
<TESTAGENT_DIR>
before invoking any sub-agent:
- Prefer a host-provided session artifact or scratch directory when one is available.
- Otherwise, in a Git worktree run
git rev-parse --path-format=absolute --git-path testagent. This returns a path in worktree-specific Git metadata, which cannot be staged or committed. - Outside Git, create a unique directory under the operating system's temporary directory.
Create the resolved directory and pass its absolute path explicitly in every
sub-agent prompt. Never create <TESTAGENT_DIR> or any intermediate state file
in version-controlled workspace content, and never modify .gitignore to hide
them.
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.
- 2d ago Changed · +28 lines 8985a80f5fd7
- 3d ago First seen · 233 lines · 44 tokens per session scan A 2e40707070ca
code-testing-generator is an agent published in the GitHub repository dotnet/skills (5,377 stars, last pushed today), licensed MIT. It adds 44 tokens to every session and 4,370 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 2026-09-03.
Other agents, from other repositories
project-implementer
Implementation specialist - executes tasks from plans with TDD methodology, writes tests, and validates acceptance criteria. Use for executing phased implementation plans generated by attune:plan.
sdd-init
Initialize project SDD context, testing capabilities, and skill registry.
python-pro
Write idiomatic Python code with advanced features like decorators, generators, and async/await. Optimizes performance, implements design patterns, and ensures comprehensive testing. Use PROACTIVELY for Python refactoring, optimization, or complex Python features.
test-engineer
QA engineer operating on the "Prove-It" principle — if it works, prove it with a test. Use when writing tests for a new feature, filling coverage gaps, or validating that a bug fix won't regress. Can read, write and edit test files. Dispatch with Task tool for isolated test work.
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.