cswin32-com

Guides struct-based COM interop in MSBuild using CsWin32 patterns. Consult when working with ComScope<T>, ComClassFactory, IComIID, IID.Get<T>(), delegate* unmanaged vtables, CoCreateInstance, or manually defining COM interfaces not in Win32 metadata (e.g. WMI IWbemLocator, IWbemServices).

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.

A high-density, expert-level COM interop guide with executable code and a clear sequenced workflow that assumes Claude's competence and avoids padding. Its one weakness is progressive disclosure: everything lives in a single long SKILL.md with no reference files to offload the deep-dive sections.

Suggestions

Move the more self-contained deep-dives (e.g. 'CS3016 CLS Compliance', 'Mocking Struct-Based COM in Tests', 'Strongly-typed handle / token wrappers') into separate reference files under references/ and link to them from a concise overview, so the main SKILL.md stays a lean entry point.

Add a short 'Quick reference' or overview block at the top summarizing the core ComScope/activate/call pattern before the detailed sections, giving readers a fast path into the material.

Keep version-sensitive notes (0.3.287 behaviour) in a clearly labeled 'Current state' or 'Deprecated/removed' subsection so they read as maintenance notes rather than inline normative guidance.

Dimension	Reasoning	Score
Conciseness	The body is dense and assumes COM/vtable competence throughout, with no padding about what COM or marshalling is; version notes ('since 0.3.287') describe current generator behavior rather than date-conditional instructions, so it is not penalized for time-sensitivity.	3 / 3
Actionability	It provides fully executable C# — manual struct definitions, ComScope/BSTR/AgileComPointer usage, activation, and ownership-transfer examples — that is copy-paste ready with specific slot indices and calling-convention guidance, not pseudocode.	3 / 3
Workflow Clarity	The 6-step Workflow is a clear, ordered sequence (metadata check → lifetime → activate → call → error contract → feature guard); this is a coding-pattern guide rather than a destructive/batch operation, so no validate-fix-retry loop is required to reach 3.	3 / 3
Progressive Disclosure	The skill is well-sectioned with internal anchor links, but it is a >50-line monolithic document with all detail inline and no reference bundle files, so content that could be split (CS3016 compliance, mocking, token wrappers) is not separated out as one-level-deep references — matching the 'content that should be separate is inline' anchor rather than the clearly-split level-3 example.	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 tightly written, third-person description that pairs a concrete capability statement with an explicit 'Consult when' trigger clause and domain-specific API terms. It is specific, complete, and distinct from sibling skills.

Dimension	Reasoning	Score
Specificity	Names multiple concrete actions — 'Guides struct-based COM interop', 'manually defining COM interfaces' — alongside specific API elements (ComScope<T>, CoCreateInstance), matching the 'lists multiple specific concrete actions' anchor rather than the partial level-2 example.	3 / 3
Completeness	It states both what ('Guides struct-based COM interop in MSBuild using CsWin32 patterns') and when ('Consult when working with ...'), with an explicit trigger clause, so it is not capped at 2 for a missing 'Use when' equivalent.	3 / 3
Trigger Term Quality	The 'Consult when working with ... CsWin32 ... CoCreateInstance ... WMI IWbemLocator, IWbemServices' clause gives good coverage of the natural terms a developer in this niche would say, not just generic jargon.	3 / 3
Distinctiveness Conflict Risk	The MSBuild + CsWin32 + struct-based COM niche with named APIs (IComIID, delegate* unmanaged vtables) is a clear, distinct trigger set 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: 10 suspicious	Warning

	Total	14 / 16 Passed

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

Reviewed: 5 days ago

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