AlertDialog

A modal decision with a primary message, safe cancel target and explicit action intent.

Root fixes alert semantics. Mask owns modality; Content traps focus, blocks outside dismissal and starts at Cancel when available. Action emits action before requesting close. Application code owns the effect; no destructive operation is performed by the prototype. Escape and Cancel request dismissal.

Root supports controlled open or uncontrolled defaultOpen. Disabled commands do not activate. Supplying open leaves the committed value with the owner; listen to openChange and provide the next value.

Parts: Root, Trigger, Content, Header, Title, Description, Footer, Cancel, Action, Mask. Header and Footer are optional, passive layout parts with empty Props/Exposes. They preserve authored children without adding commands or state.

The desktop composition follows the pinned Neo-Brutalist source: a 5px-radius panel with 24px padding, 8px-spaced heading and description, and intrinsic-width actions aligned right with a 12px gap. Footer uses natural reverse wrapping when its contents no longer fit. This is not the upstream 640px switch to full-width reverse columns; narrow-screen text centering and the 545–639px panel width remain different. The existing zero-duration transitions, theme-relative focus offset and dark palette remain Proto UI behavior/extensions. Upstream small-size and Media parts are not exposed.

Draft source implementation. Full native/GPUI, compiler, packed-consumer, visual and independent acceptance remain pending; this page does not claim Finf completion.