options property

Values worth offering for a knob whose type cannot enumerate itself.

An enum parameter needs none — its constants are read off the declaration, so a list here would be the same facts twice and free to drift. That reading is bounded, and the bound is worth knowing: the entry point's own file, the files it imports directly, and the packages of the same checkout — a shared config package included. An enum outside all three is reported by name rather than drawn, and a list here does not rescue it: the values would be offered for a control that is not there.