author-component

license	MIT
name	author-component
description	Create or review Blazor components (.razor files) with correct architecture. USE FOR: writing new Blazor components that do NOT involve JavaScript interop, implementing parameters and EventCallback, RenderFragment slots, component lifecycle (OnInitializedAsync, OnParametersSet), async patterns, IAsyncDisposable, CancellationToken, CSS isolation, code-behind. DO NOT USE FOR: creating new projects (use create-blazor-project), JavaScript interop or calling browser APIs from Blazor (use use-js-interop), forms and validation (use collect-user-input), prerendering issues (use support-prerendering), HTTP data fetching patterns (use fetch-and-send-data), coordinating state between unrelated components (use coordinate-components).

Author Blazor Component

Core Rules

• Data flows down via [Parameter]. Events flow up via EventCallback<T> (never Action/Func).
• Never mutate [Parameter] properties. Copy to a private field in OnParametersSet.
• Use [Parameter] public T Prop { get; set; } — never required or init (causes BL0007).
• Use [EditorRequired] for required parameters.
• Handle all states: loading, empty, loaded, error — each with @if/@else.
• Use @key on repeated elements in loops for efficient diffing.
• Use IReadOnlyList<T> (not IEnumerable<T>) for collection parameters.