cswin32-interop

Guides CsWin32 P/Invoke interop in MSBuild. Consult when working with the PInvoke class, Windows.Win32 namespaces, FEATURE_WINDOWSINTEROP, HANDLE/HMODULE/HRESULT types, BufferScope<T>, replacing [DllImport] with CsWin32, or conditioning Windows-only code for source builds.

Quality

96%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Quality

Content

92%

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

Highly actionable and dense reference material with a strong validation checkpoint for source builds. Its main weakness is progressive disclosure: it is a single long file that could move detailed tables into reference files.

Suggestions

Move the constant-replacement mapping and guard-selection table into a references/ file (e.g. REFERENCES.md) and link to it from SKILL.md to reduce inline bulk and improve progressive disclosure.

Consider extracting the FILETIME-conversions and BufferScope<T> detail into a separate reference, keeping SKILL.md as an overview with one-line pointers.

Add a short numbered end-to-end migration workflow at the top (replace DllImport -> gate -> blittable signature -> verify builds) that ties Rules 1-6 to the source-build verification step.

Dimension	Reasoning	Score
Conciseness	Dense, project-specific rules with no basic-concept padding; assumes C#/MSBuild competence and spends tokens only on knowledge Claude would not already have (file paths, guard tables, type mappings).	3 / 3
Actionability	Provides executable code (Dual Guard Pattern, BufferScope<T> usage), copy-paste commands ('dotnet msbuild MSBuild.SourceBuild.slnf /p:DotNetBuildSourceOnly=true'), and exact type/constant mappings.	3 / 3
Workflow Clarity	The 'Source-Build Verification (REQUIRED before pushing)' section gives an explicit two-build sequence with a warning checklist (IDE0005/IDE0051/CA1823/CS1587), a clear validation feedback loop before destructive pushes.	3 / 3
Progressive Disclosure	Well-sectioned but monolithic: ~186 lines with inline content (constant-replacement table, guard-selection table, FILETIME section) that could be split into reference files; no internal bundle references exist to offload detail.	2 / 3
	Total	11 / 12 Passed

Description

100%

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

A specific, third-person description with an explicit 'Consult when' trigger clause and a tight, distinctive niche. It avoids fluff and gives Claude clear firing conditions.

Dimension	Reasoning	Score
Specificity	Lists multiple concrete actions and types—'replacing [DllImport] with CsWin32', 'conditioning Windows-only code for source builds', plus HANDLE/HMODULE/HRESULT/BufferScope<T>—rather than vague language.	3 / 3
Completeness	Explicitly states what ('Guides CsWin32 P/Invoke interop in MSBuild') and when ('Consult when working with...'), satisfying both halves with an explicit trigger clause.	3 / 3
Trigger Term Quality	Covers natural triggers a developer in this domain would actually say: 'PInvoke class', 'Windows.Win32 namespaces', 'replacing [DllImport] with CsWin32', 'Windows-only code', 'source builds'.	3 / 3
Distinctiveness Conflict Risk	Narrow niche (CsWin32 P/Invoke interop in MSBuild, general layer) with distinct technical triggers unlikely to fire for unrelated skills.	3 / 3
	Total	12 / 12 Passed

Validation

87%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 14 / 16 Passed

Validation for skill structure

Criteria	Description	Result
frontmatter_unknown_keys	Unknown frontmatter key(s) found; consider removing or moving to metadata	Warning
relative_links	Relative link issues: 9 suspicious	Warning

	Total	14 / 16 Passed

Repository: dotnet/msbuild
Path: .github/skills/cswin32-interop/SKILL.md
Commit: c88db8e

Reviewed: 5 days ago

Table of Contents

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