Continuity of state · The visibility · Element
The surface
Where the context appears.
The part
What it is
In the agent’s primary view during the conversation, not in a system they would have to open.
A second window opened during a live call is a window that is not opened.
The smallest level
The attributes it carries
Each attribute is one of the framework’s shared types. What a date is, and how it is written, is defined once for the whole model — the note here says what it means in this particular place.