Composer

A prompt field and send or stop controls in one surface.

This is an Open Code component: it installs into your application, not as a separate Agent runtime package. The names below assume prefix Ui.

Install

In a Flutter application with the project-local CLI configured:

dart run remix_cli:remix init --prefix Ui --preset fortal
dart run remix_cli:remix add composer_recipe

Use --preset vanilla when initializing a Vanilla-preset application. Do not reinitialize an existing application with a different preset. Installing composer_recipe includes its component and required theme/control dependencies. Use add composer instead when you want the bare component and will provide styles.

Import ui/ui.dart from your application and use the scope for your preset:

• Fortal: UiScope(child: ...).
• Default: UiThemeScope(theme: const UiThemeData.light(), child: ...) (or UiThemeData.dark() for a dark theme).

Behavior

Wire onSubmit to your runner and onStop to cancellation. The host owns running state and submission eligibility. Enter submits, Shift+Enter inserts a newline, and active IME composition does not submit. Keep model-provider calls, cancellation, and persistence outside the component.

Recipe bundle

uiAgentComposerRecipe() returns these styles:

Pass the bundle's styles to the corresponding component parameters. Each factory accepts same-named overrides, merged after the preset defaults. Child-control styles must be passed through unchanged so hover, focus, and disabled styles resolve in the child's context.

Review and customize

The dashboard's Workspace → Chat demonstrates this surface alongside the other Agent components. Its responses and tool activity are simulated locally. Edit your installed source to customize it; dart run remix_cli:remix add composer_recipe --diff previews authored-source differences without overwriting local edits.