ALWAYS USE for test work that requires changes: write, add, generate, repair, or strengthen tests for existing code in xUnit, MSTest, NUnit, pytest, Vitest/Jest, Go, or another framework. Includes regression cases, failing or flaky tests, coverage-driven additions, and audit-then-fix requests. Focused work stays direct; broad or multi-stage work invokes test-engineer.
Install
npx skills add dotnet/skills --skill code-testingnpx skills add dotnet/skills --skill code-testing -a claude-code -gnpx skills add dotnet/skills --skill code-testing -a codex -ggemini skills install https://github.com/dotnet/skills.git --path plugins/dotnet-test/skills/code-testinggh skill install dotnet/skills code-testinggit clone --depth 1 https://github.com/dotnet/skills /tmp/dotnet__skills
mkdir -p ~/.claude/skills ~/.agents/skills
cp -R /tmp/dotnet__skills/plugins/dotnet-test/skills/code-testing ~/.claude/skills/code-testing # Claude Code
cp -R /tmp/dotnet__skills/plugins/dotnet-test/skills/code-testing ~/.agents/skills/code-testing # Codex, Cursor, Gemini CLI, Copilot, OpenCode