Blazor

Blazor conventions — STARTER

Same shape as dotnet-wpf. This is a starting point: extend it as the Blazor codebase and its conventions settle, and split the checklists into references/ once they grow.

Conventions this skill needs — read them from the repository's agent file

Same rule as dotnet-wpf: values live only in the repository's AGENTS.md / CLAUDE.md; this skill stores none. Confirm before implementing; infer from nearby code and flag it in the report when absent.

• Hosting model and render modes in use (Server / WebAssembly / Auto)
• Target framework, solution path, main project paths
• Component base classes and state-management pattern
• DI container and lifetimes (on Server, scoped = per circuit; on WebAssembly, scoped behaves as singleton)
• JS interop conventions
• Test framework, mocking library, and test project paths (bUnit + xUnit/NUnit, or none)
• Folder layout
• User-facing error contract
• Build, format, and test commands (defaults in the Validation section below)

Workflow parameter owned by this skill: plan-pause file threshold = 8. The agent file may override it.

What to read, when

• Feature or bug work → the checklist below (single section until it grows)
• Before any build or test step → the validation section below

Checklist

Features:

• One component, one responsibility; keep logic in the partial class or a service, not in markup.
• Parameters are inputs; do not mutate [Parameter] values inside the component.
• Use EventCallback for child-to-parent communication; cascading values only for shared context.
• Async lifecycle methods (OnInitializedAsync, OnParametersSetAsync) await their work; no blocking waits.
• Call StateHasChanged only when state changes outside the normal event/lifecycle path (timers, external events).
• Respect render-mode boundaries: prerendering runs without JS interop; interactive code must not assume it ran during prerender.
• Dispose subscriptions and timers via IDisposable / IAsyncDisposable.

Bugs — where Blazor defects usually hide:

• UI not updating: state changed on a non-UI path without StateHasChanged, or in a component whose parameters did not change
• double execution: OnInitializedAsync runs during prerender and again when the component becomes interactive
• JS interop called during prerender, or after the circuit or component is disposed
• DI lifetime confusion between Server and WebAssembly hosting
• stale async results overwriting newer component state
• event-handler re-entrancy and missing await
• missing @key on rendered lists causing wrong component reuse

Validation

1. Format / analyzers: dotnet format <sln> --verify-no-changes
2. Build: dotnet build <sln> -c Debug --nologo
3. Tests: dotnet test <tests> --no-build (bUnit tests run on any OS)
4. Runtime check in a browser for rendering, interop, and render-mode behavior, when an environment is available

Blazor projects build and test on any OS; only step 4 needs a runnable app. Never mark a step as passed if it did not execute.