When to use

Use this skill when:

Creating an MSIX installer from a built app for distribution or testing
Packaging any Windows app — GUI apps, console apps, CLI tools, services, or background processes
Signing a package with a development or production certificate
Bundling the Windows App SDK runtime for self-contained deployment

Prerequisites

What you need depends on the input:

Project mode (winapp package MyApp.csproj): an explicit .csproj for a packaged app (EnableMsixTooling=true with a Package.appxmanifest). winapp publishes it and packages the output.
Folder mode (winapp package ./bin/Release): built app output in a folder (e.g., bin/Release/, dist/, build/) plus a Package.appxmanifest in the current directory, passed via --manifest, or in the folder.
Certificate (optional, both modes) — devcert.pfx from winapp cert generate for signing.