migrate-xunit-to-xunit-v3

migrate-xunit-to-xunit-v3 is a skill for Claude Code, Codex from managedcode/dotnet-skills. It costs 149 tokens per session (3,521 once invoked), scanned A, original, MIT.

A guide to moving .NET test projects from xUnit.net v2 to xUnit.net v3. xUnit.net is a framework for writing and running automated tests in .NET.

In plain words
What is it for?
Use it to update xUnit package references, fix code that no longer compiles, and verify that the migrated test projects pass.
Why use it?
A test-framework upgrade can change package names, APIs, and build behavior, causing compilation failures even when the tests are meant to keep the same results. This keeps the migration focused on xUnit v2 projects.

Skill for Claude CodeCodex

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

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-xunit-v3
Any agent
npx skills add managedcode/dotnet-skills --skill migrate-xunit-to-xunit-v3
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-xunit-v3

README.md
[![agentmods](https://agentmods.dev/badge/skills/managedcode/dotnet-skills/migrate-xunit-to-xunit-v3.svg)](https://agentmods.dev/skills/managedcode/dotnet-skills/migrate-xunit-to-xunit-v3)
Your own site
<a href="https://agentmods.dev/skills/managedcode/dotnet-skills/migrate-xunit-to-xunit-v3"><img src="https://agentmods.dev/badge/skills/managedcode/dotnet-skills/migrate-xunit-to-xunit-v3.svg" alt="Measured on agentmods" height="20"></a>
Per session 149 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,521 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 5.1 $0.00149 $0.03521
Opus 5 $0.00075 $0.01760
Sonnet 5 $0.00030 $0.00704
Haiku 4.5 $0.00015 $0.00352

Measured today against content hash 265995747a72, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

migrate-xunit-to-xunit-v3 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-xunit-v3/SKILL.md · 292 lines

How it starts

The opening of the file, as written. The whole thing — 292 lines — stays where its author put it; the contents beside it link to each section on GitHub.

xunit.v3 Migration

Migrate .NET test projects from xUnit.net v2 to xUnit.net v3. The outcome is a solution where all test projects reference xunit.v3.* packages, compiles cleanly, and all tests pass with the same results as before migration.

When to Use

  • Upgrading test projects from xunit (v2) packages to xunit.v3
  • Resolving compilation errors after updating xunit package references to v3

When Not to Use

  • Migrating between test frameworks (e.g., MSTest or NUnit to xUnit.net) — different effort entirely
  • Migrating from VSTest to Microsoft.Testing.Platform — use migrate-vstest-to-mtp
  • The projects already reference xunit.v3 — migration is done

Inputs

Input Required Description
Test project or solution No Discover .csproj, .sln, .slnx, central props, and source in the current working directory; ask only if none are found or the target is ambiguous

Workspace and Completion Contract

  • Skill activation is not completion. For migrate/fix/update requests, inspect the staged files, edit them, and run tests in the same task.
  • The skill base directory contains only guidance. Search the current working directory and open paths exactly as returned. If a tool rejects a path just found by search, retry with another available reader/editor instead of concluding that files are missing.
  • Do not ask the user to provide a path while workspace discovery can find it.
  • Inventory project/central package files and all affected source in one pass. A package-only migration is incomplete when v2-only APIs remain.
  • End with the detected source version and runner, exact package compatibility set, files changed, discovered/passed/failed/skipped counts, and any platform-specific result. A build without test discovery is not success.
  • Package validity is empirical: record the configured feed query or resolved package graph and a successful restore. In the final result, say how the selected exact versions were proven available; do not merely name a version and leave a judge or user to infer whether it exists.

Read the full file on GitHub · 292 lines

Files

What ships with it

1 file 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 · +64 lines · +38 tokens per session 265995747a72
  2. 2d ago First seen · 228 lines · 111 tokens per session scan A 20190be954b5

Subscribe to this mod's changes

migrate-xunit-to-xunit-v3 is a skill published in the GitHub repository managedcode/dotnet-skills (477 stars, last pushed yesterday), licensed MIT. It adds 149 tokens to every session and 3,521 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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