FeatureChecker

Automated, project-wide code coverage and CRAP (Change Risk Anti-Patterns) score analysis for .NET projects with existing unit tests. Auto-detects solution structure, runs coverage collection via `dotnet test` (supports both Microsoft.Testing.Extensions.CodeCoverage and Coverlet), generates reports via ReportGenerator, calculates CRAP scores per method, and surfaces risk hotspots — complex code with low test coverage that is dangerous to modify. Use when the user wants project-wide coverage analysis with risk prioritization, coverage gap identification, CRAP score computation across an entire solution, or to diagnose why coverage is stuck or plateaued and identify what methods are blocking improvement. DO NOT USE FOR: targeted single-method CRAP analysis (use crap-score skill), writing tests, running tests without coverage collection, applying test filters, producing TRX reports, or troubleshooting test execution (use run-tests for all of these).

Primary router skill for broad .NET work. Classify the repo by app model and cross-cutting concern first, then switch to the narrowest matching .NET skill instead of staying at a generic layer. USE FOR: general .NET requests without a narrower framework; C# implementation, debugging, review, or refactoring; routing to framework and tooling skills. DO NOT USE FOR: unrelated stacks; tasks already covered by a narrower .NET skill. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.

Reference data for .NET test framework detection patterns, assertion APIs, skip annotations, setup/teardown methods, and common test smell indicators across MSTest, xUnit, NUnit, and TUnit. Loaded by test analysis skills (test-anti-patterns) as framework-specific lookup tables.

Use the Microsoft.Extensions stack correctly across Generic Host, dependency injection, configuration, logging, options, HttpClientFactory, and other shared infrastructure patterns. USE FOR: wiring dependency injection, configuration, logging, or options; introducing Generic Host patterns into non-web .NET apps; cleaning up service registration, typed HTTP. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.

Write modern, version-aware C# for .NET repositories while staying compatible with the repo's target framework and language-version policy. USE FOR: modern idiomatic C# code; language-version compatibility decisions; upgrading or reviewing C# feature usage across versions. DO NOT USE FOR: non-C# .NET languages such as F# or VB; analyzer-only or formatter-only setup with no language feature choice. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.

Create or reorganize .NET solutions with clean project boundaries, repeatable SDK settings, and a maintainable baseline for libraries, apps, tests, CI, and local development. USE FOR: creating a new .NET solution or restructuring an existing one; setting up Directory.Build.props, shared package management, or repo-wide defaults; defining project. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.

Runs .NET tests with dotnet test. Use when user says "run tests", "run my tests", "run these tests", "execute tests", "dotnet test", "test filter", "filter by category", "filter by class", "combine filters", "run only specific tests", "integration tests", "unit tests", "tests not running", "hang timeout", "blame-hang", "blame-crash", "crash dump", "TRX report", "TRX", "test report", "generate TRX", "TUnit", "treenode-filter", "target framework", "multi-TFM", or needs to detect the test platform (VSTest or Microsoft.Testing.Platform), identify the test framework, apply test filters, or troubleshoot test execution failures. Covers MSTest, xUnit, NUnit, and TUnit across both VSTest and MTP platforms. Also use for --filter-class, --filter-trait, --report-trx, --logger trx, --blame-hang-timeout, and other platform-specific filter and reporting syntax. DO NOT USE FOR: writing or generating test code, CI/CD pipeline configuration, or debugging failing test logic.

Quick pragmatic detection-focused review of .NET test code for anti-patterns that undermine reliability and diagnostic value. Use when asked to audit test quality, investigate flaky or coupled tests, find duplication or magic values, or when tests pass but don't actually verify anything. Best for identifying and prioritizing issues in existing tests with severity-ranked findings and targeted remediation guidance. Catches assertion gaps, swallowed exceptions, always-true assertions, flakiness indicators, test coupling, over-mocking, naming issues, magic values, duplicate tests, and structural problems. Do NOT use for direct MSTest API rewrites or implementation-only fixes (for example swapped Assert.AreEqual argument order or converting `DynamicData` from `IEnumerable<object[]>` to `ValueTuple`) — use writing-mstest-tests instead. For a deep formal audit based on academic test smell taxonomy, use exp-test-smell-detection instead. Works with MSTest, xUnit, NUnit, and TUnit.