UpdateHints

If you want that action hints to be changed, you need to call method UpdateHints() from interaction script.

For example: In this script, hint depends on activityState, which is changed in OnInteractPrimary method.

ActivityState activityState = ActivityState.Off;

bool UsePrimaryActionHint() => true;

string GetPrimaryHintText() => activityState == ActivityState.On ? "Turn Off" : Turn On";

void OnInteractPrimary()
{
    GetCurrentPrimaryAction().action.Invoke();
    activityState = (activityState == ActivityState.On ? ActivityState.Off : ActivityState.On);
}

To make hints change, and show actual information, use method UpdateHints():

ActivityState activityState = ActivityState.Off;

bool UsePrimaryActionHint() => true;

string GetPrimaryHintText() => activityState == ActivityState.On ? "Turn Off" : Turn On";

void OnInteractPrimary()
{
    GetCurrentPrimaryAction().action.Invoke();
    activityState = (activityState == ActivityState.On ? ActivityState.Off : ActivityState.On);
    UpdateHints();
}