If a component has a human user interface, it must be able to establish whether a given human user performed a particular action; control elements that cannot support this are to be listed in the component documentation (the base requirement is at SL 1). RE 1 (SL 4): the same determination for every user, human, software process or device.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.