WinUI 3 App Development Assistant
Guides C# WinUI 3 development from environment setup through deployment.
The skill distinguishes audit-only work from machine-changing setup and requires confirmation for diagnostic setup scenarios. However, the setup flow can enable Developer Mode and perform elevated installation of Visual Studio and components, without complete pre-change confirmation, rollback guidance, least-privilege detail, or sensitive-data handling guidance. Microsoft/OpenAI source attribution is indicated, but no verifiable per-skill license is supplied.
The workflow gives concrete steps, commands, packaging distinctions, and failure branches, and requires template, build, and window-launch checks. Static review cannot reproduce execution, some indexed reference files are absent from the supplied material, and abnormal-input and dependency-version coverage is limited, so the score remains conservatively below the static ceiling.
The Windows-only WinUI 3/C# audience and scenarios are clear, with routes for setup, development, review, and troubleshooting. Non-fit boundaries, semantic trigger precision, and Chinese-language support are not explicit. Core references rely on Microsoft/GitHub services that may be difficult to reach from mainland China, with no stated fallback, so points are deducted.
The skill uses a readable task-classification flow, a narrow-reference index, and progressive disclosure; its name and description broadly match its capability. However, the individual skill license is unknown, and versioning, changelog, maintenance ownership, and update path are not clear. Several indexed targets are also missing from the supplied evidence.
It provides a substantial framework for WinUI setup, project selection, UI guidance, build, and launch verification, so the core advisory task is plausibly supported. Static evidence includes no verified representative outputs, test results, or actual build/launch records, and external prerequisites and missing references may require substantial user follow-up.
Concrete commands, configuration, source attributions, and auditable workflow requirements provide some traceability. There is no committed test suite, CI result, third-party execution evidence, or independent reproduction in this review, so only limited static evidence credit is warranted.
- The setup flow may enable Developer Mode and install software with elevation; obtain explicit confirmation of the affected machine and prepare a rollback or uninstall path before execution.
- The skill depends on Windows, Visual Studio, WinGet, .NET, and the Windows App SDK. Compatibility is not demonstrated, and no complete offline or mainland-China network fallback is documented.
- Several referenced files were not included in the supplied evidence; confirm that they exist and match the assessed revision before relying on those routes.
- The individual skill has no supplied license, version history, maintenance owner, or changelog.
What it does & when to use it
This skill supports developers building WinUI 3 desktop applications with C# and the Windows App SDK. It covers environment checks, project creation, XAML UI, navigation, windows, theming, accessibility, responsive layouts, performance, lifecycle, and deployment. It classifies each request and routes the work to relevant reference material, prioritizing Microsoft Learn, WinUI Gallery, and WindowsAppSDK-Samples. For new applications and machine preparation, it provides a WinGet- and dotnet-template-based bootstrap flow.
It classifies tasks as environment/setup, new-app bootstrap, design, implementation, review, or troubleshooting. When applicable, it runs the bundled WinGet configuration, checks whether the dotnet winui template is available, and scaffolds projects with dotnet new winui. It helps choose packaged or unpackaged deployment, and gives implementation guidance for native WinUI controls, CommandBar surfaces, theming, windows, responsive layouts, accessibility, performance, lifecycle, notifications, and deployment. After creating or changing an app, it requires building and launching it, then verifying objective startup signals such as a responsive top-level window.
- A developer needs to prepare a Windows machine and audit its WinUI 3 readiness.
- A developer wants to create a new C# WinUI 3 desktop application and select its packaging model.
- A developer needs guidance on navigation, title bars, multi-window behavior, or responsive page layouts.
- A developer is reviewing an existing WinUI application's structure, bindings, themes, accessibility, or performance.
- A developer is troubleshooting XAML compilation, startup, lifecycle, notification, or deployment issues.
Pros & cons
- Covers the workflow from environment preparation and scaffolding through launch verification.
- Strongly favors native WinUI controls and Fluent design guidance.
- Provides concrete rules for packaging, responsive behavior, theming, accessibility, and startup verification.
- Organizes detailed guidance through task-specific reference routes.
- It is specialized for Windows, C#, WinUI 3, and the Windows App SDK rather than general desktop development.
- Some flows can change the machine by enabling Developer Mode or installing Visual Studio components.
- The source material provides no test suite or independent platform validation results.
- The repository is marked deprecated, and the contents of this skill's LICENSE.txt were not provided, so its license status cannot be confirmed.
How to install
In Codex, run $skill-installer winui-app to install this curated skill. Restart Codex afterward so the skill is loaded. The supplied README does not document another complete installation method.
How to use
With the skill installed in Codex, provide a concrete WinUI 3 or Windows App SDK request, for example: “Create a C# WinUI 3 app named ExpenseTracker using the default packaging model, then verify the build and launch.” If no app name is supplied, the skill derives a short PascalCase name from the request.
Compared to similar skills
The skill explicitly prioritizes Microsoft Learn, WinUI Gallery, and WindowsAppSDK-Samples, and prefers native WinUI controls. The source material does not provide a direct comparison with other skills or frameworks.