context — what a case sends: the bytes of the position's knowledge the chat speaks from, against the bytes of the source row it was made from (ext positioning)
action — how far a door is from a hop: the steps from a door's first step to the first step that opens a hop of the sale (ext positioning)
grade — where the answer is checked: the assure threshold of every graded move and the class's grade path (exact by code, or System One's four questions) (ext positioni
trace — what is provable: the moves whose hop is carried as an envelope on the pipe, over all moves; the nodes whose every name resolves to a set, over all nodes (ext p