Function sheet_dimension_schema 

pub fn sheet_dimension_schema() -> Value

The Sheet dimension dialog’s schema, in the inputParamsSchema vocabulary the shared form engine renders — so the dialog is not hand-written, exactly like the sheet’s and the placement’s.

anchors is a reference_selection: the form draws it as the reference rows every feature’s references are drawn as, its Select button opens the reference picker on the sheet’s paper, and each row’s ✕ drops that anchor. With no label its row reads the prettified key, “Anchors”.

The last four fields are the tolerance block (SheetTolerance), the PMI dimension form’s own.