migrate-xunit-to-mstest

migrate-xunit-to-mstest is a skill for Claude Code, Codex from managedcode/dotnet-skills. It costs 141 tokens per session (3,474 once invoked), scanned A, original, MIT.

A conversion guide for changing .NET tests from xUnit.net to MSTest v4 while keeping the same target framework and test platform.

In plain words
What is it for?
It helps migrate xUnit test projects, update their packages and source code, and verify that the same tests are found and pass.
Why use it?
It maps test attributes, assertions, fixtures, output, skips, and parallel execution so the converted tests keep their intended behavior.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/managedcode/dotnet-skills/migrate-xunit-to-mstest
Any agent
npx skills add managedcode/dotnet-skills --skill migrate-xunit-to-mstest
Clone the repo
git clone --depth 1 https://github.com/managedcode/dotnet-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 migrate-xunit-to-mstest

README.md
[![agentmods](https://agentmods.dev/badge/skills/managedcode/dotnet-skills/migrate-xunit-to-mstest.svg)](https://agentmods.dev/skills/managedcode/dotnet-skills/migrate-xunit-to-mstest)
Your own site
<a href="https://agentmods.dev/skills/managedcode/dotnet-skills/migrate-xunit-to-mstest"><img src="https://agentmods.dev/badge/skills/managedcode/dotnet-skills/migrate-xunit-to-mstest.svg" alt="Measured on agentmods" height="20"></a>
Per session 141 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,474 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00141 $0.03474
Opus 5 $0.00071 $0.01737
Sonnet 5 $0.00028 $0.00695
Haiku 4.5 $0.00014 $0.00347

Measured today against content hash e43e9a0be738, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

migrate-xunit-to-mstest 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 today.

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.

catalog/Platform/Official-DotNet-Test-Migration/skills/migrate-xunit-to-mstest/SKILL.md · 190 lines

How it starts

The opening of the file, as written. The whole thing — 190 lines — stays where its author put it; the contents beside it link to each section on GitHub.

xUnit -> MSTest Migration

Convert xUnit.net v2 or v3 tests to MSTest v4 without changing the target framework or test platform. A successful migration builds, discovers the same tests, and preserves pass/fail results and execution semantics.

Scope

Use this skill only when the project contains xUnit packages or source and the user wants MSTest. If the project already uses MSTest and contains no xUnit tests, report that no framework migration is needed and make no changes.

Do not combine this framework conversion with a target-framework upgrade or VSTest/MTP migration. Complete and verify one migration before starting another.

Workspace Contract

  • Continue after skill activation. Search the current working directory for the staged project and source; never look for user files under this skill's base directory.
  • Open the literal paths returned by glob/search. If one reader or patch tool rejects a path that was just found, retry with another available tool. Do not ask the user for a path until current-workspace discovery is exhausted.
  • Classify by the requested deliverable: "convert this project" means edit, build, and test; "give me a plan" or "how would I convert it?" means answer. Do not replace execution with "please provide the files" when files are present.
  • The final response must state the source xUnit version, preserved runner, changed files, each high-risk semantic mapping applied, and actual test counts. Assertions about fixture lifetime, Owner mapping, cancellation, or parallelization must be visible in the resulting source, not only prose.

Response Mode

  • Full migration request: inspect the project, make the edits, build, and run tests. Do not stop after giving a plan.
  • Focused compile error or API question: inspect the relevant code and apply only that mapping. Do not narrate the entire workflow.
  • Unsupported target framework: stop before changing packages. MSTest v4 requires .NET 8+ or .NET Framework 4.6.2+ for test applications; offer a separately approved TFM upgrade or MSTest v3 as the intermediate target.

Read the full file on GitHub · 190 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. today Changed · +25 lines · +28 tokens per session e43e9a0be738
  2. yesterday First seen · 165 lines · 113 tokens per session scan A 292a707d4f3a

Subscribe to this mod's changes

migrate-xunit-to-mstest is a skill published in the GitHub repository managedcode/dotnet-skills (477 stars, last pushed today), licensed MIT. It adds 141 tokens to every session and 3,474 once invoked, about $0.0007 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.

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