uno-mvux-commands

# MVUX Commands — Agent Skill ## Workflow > **Docs lookup:** call `uno_platform_docs_search(...)` first, then `uno_platform_docs_fetch(sourcePath="…")` using the `sourcePath` field from a result (a relative `.md` path; add the result's `anchor` for a section). Never pass a URL, a `.html` link, or a hand-built path. ### Step 1: Fetch the Commands Documentation Search for and fetch the commands documentation: ``` uno_platform_docs_search("MVUX commands automatic generation method invocation") ``` Primary documentation pages: - **Commands Reference**: `external/uno.extensions/doc/Learn/Mvux/Advanced/Commands.md` - **Commands How-To**: `external/uno.extensions/doc/Learn/Mvux/Walkthrough/Commands.howto.md` Fetch the reference page for complete details: ``` uno_platform_docs_fetch(sourcePath="external/uno.extensions/doc/Learn/Mvux/Advanced/Commands.md") ``` ### Step 2: Understand Implicit Command Generation From the fetched docs, any public method on a Model automatically becomes a command in the generated ViewModel. The reference page covers: - Basic command generation rules - Using `CommandParameter` from XAML - Additional feed parameters (method parameter names matching feed property names) - The `[ImplicitCommands]` attribute to enable/disable generation ### Step 3: For How-To Walkthroughs For step-by-step examples: ``` uno_platform_docs_fetch(sourcePath="external/uno.extensions/doc/Learn/Mvux/Walkthrough/Commands.howto.md") ``` This covers creating basic commands, using feed values in commands, can-execute logic, and disabling command generation. ### Step 4: For Explicit Command Creation If the user needs manual control over commands, the reference page has an "Explicit command creation" section covering `Command.Create(...)`. ## Critical Rules - **Feed parameter injection works for any feed type** (`IFeed<T>`, `IListFeed<T>`, `IState<T>`, `IListState<T>`) — the matching parameter receives a *snapshot* of the current value. - **But you can only mutate writable types from inside a command body.** `IState<T>` and `IListState<T>` expose `UpdateAsync` / `AddAsync` / `RemoveAsync`. `IFeed<T>` and `IListFeed<T>` are **read-only** — calling `.Update(...)`, `.UpdateAsync(...)`, `.AddAsync(...)`, or `.RemoveAsync(...)` on an injected `IListFeed`/`IFeed` is a compile error. - If a command needs to mutate a collection, the property on the Model must be `IListState<T>` (not `IListFeed<T>`); convert with `ListState.FromFeed(this, sourceFeed)` if needed. - **When mutating via `UpdateAsync`, the updater must be pure** — derive the new value solely from the `current` value, with no captured external state or side effects. See [[uno-mvux-state-basics]] and [[uno-mvux-liststate]] for details. ## Key Principles (Stable) - Any public method on a `*Model` partial record generates a command in the ViewModel - Commands are automatically `IAsyncCommand` — they handle async properly - Feed parameter injection: a method parameter whose name/type matches a Feed property gets the current feed value injected - Use `[ImplicitCommands(false)]` on a Model to disable automatic generation - Commands are bound in XAML via `Command="{Binding MethodName}"` - The method name becomes the command name (e.g., `Save()` → `Save` command) ## Related Skills - [[uno-mvux-state-basics]] — States that commands often update - [[uno-mvux-feed-basics]] — Feeds whose values commands can consume - [[uno-mvux-selection]] — Selection-aware commands