MilanoViewBuilder

Declares (or overrides) a custom action for this surface: the name, parameter shape, optional success result type, and optional failure payload type join the granted set for this builder only. Declarations type the payload; meaning is assigned by this surface's action handler.

The view's action handler; required when the document uses custom actions.

Grants only the listed custom actions to this surface: a document binding any other custom action fails at the gate with a SchemaViolation (rule "action-capability"). Built-in dollar actions are contract, not capabilities, and are always available.

Building is asynchronous: the document is parsed and validated in full, then the state data provider is awaited and its values are validated against the document's declarations. Throws typed MilanoBuildExceptions; provider failures propagate unchanged.

Supplies fixed context values for the keys the document declares.

Supplies an observable context source (see MilanoContextHandle).

The serialization seam; the platform layer binds it to the main thread.

Declares (or overrides) a host function for this surface (contract 2.1): its argument types in order and its return type join the vocabulary's declarations for this builder only. The engine's function handler resolves it by name like any other.

Host-chosen name attached to this view's observability reports.

Per-view override of the engine's default unknown-type policy.