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

86%

Does it follow best practices?

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Securityby

Passed

No findings from the security scan

Quality

Content

82%Weight 40%Scale 1-5

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

A dense, highly actionable COM interop guide with executable examples, a clear workflow, and well-organized sections. It is mostly token-efficient and structures references one level deep, though a few explanatory sections could be trimmed and the manual-struct workflow lacks explicit validation checkpoints.

Suggestions

Tighten the 'IComIID across TFMs' and 'CS3016 CLS Compliance' sections to the essential version-gated rules; the historical polyfill/removal detail reads as context Claude largely doesn't need.

Add an explicit validation checkpoint to the manual-struct workflow (e.g. 'build and confirm the vtable slot indices compile against the IDL order') to catch stack-corruption bugs from wrong calling conventions or slot counts.

Consider moving the detailed typedef/token-wrapper table into a reference file or collapsing it to the single IsNil rule, keeping the body focused on the COM-specific layer.

Dimension	Reasoning	Score
Conciseness	Largely lean and assumes Claude's competence, packing dense, domain-specific rules without padding; a few sections (e.g. the IComIID across TFMs and CS3016 explanations) are somewhat discursive and could be tightened.	4 / 5
Actionability	Provides copy-paste-ready C# examples covering the common cases (ComScope usage, ownership transfer, CoCreateInstance/ComClassFactory activation, BSTR handling, mock CCW bridge) with concrete, executable patterns and specific slot-index rules.	5 / 5
Workflow Clarity	The Workflow section lays out a clear 6-step sequence with concrete decisions, and the migration/error-parity sections include feedback guidance; however, there are no explicit validation checkpoints (e.g. build/verify after defining a struct) for the risky manual-struct definition path.	4 / 5
Progressive Disclosure	Well-organized into focused sections with one-level-deep references to source files and a clearly signaled paired skill; no bundle files exist, so all detail is inline, which is appropriate for the scope but leaves minor organization gaps where sub-rules could be factored.	4 / 5
	Total	17 / 20 Passed

Description

90%Weight 40%Scale 1-5

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 highly specific, well-structured description that clearly states what the skill does and when to consult it, with concrete trigger types and scenarios. It uses third person and avoids vague fluff while carving out a distinct niche from its paired skill.

Dimension	Reasoning	Score
Specificity	Names the domain (struct-based COM interop in MSBuild via CsWin32) and lists multiple concrete actions and types — ComScope<T>, ComClassFactory, IComIID, IID.Get<T>(), delegate* unmanaged vtables, CoCreateInstance, and manually defining COM interfaces — for comprehensive coverage.	5 / 5
Completeness	Explicitly answers 'what' (guides struct-based COM interop using CsWin32 patterns) and 'when' ('Consult when working with...') with concrete trigger phrases naming the relevant APIs and scenarios.	5 / 5
Trigger Term Quality	Strong technical keyword coverage (ComScope, CoCreateInstance, IWbemLocator, WMI) that a user working in this niche would naturally say, but it leans on internal type names rather than common synonyms, missing a few natural phrasings.	4 / 5
Distinctiveness Conflict Risk	Occupies a clear niche (struct-based COM interop in MSBuild) with distinct, specialized triggers and even references a paired skill for the general P/Invoke layer, minimizing conflict risk.	5 / 5
	Total	19 / 20 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: b75ae9e

Reviewed: 1 day ago

Table of Contents

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