Content to be inserted into slots doesnt make sense under props, as they aren't passed like attributes. But these could possibly be put on the same level as props, taking into account named slots.

props:
  text:
  background:
children:
  namedslot1:
  namedslot2:

Or, the children could be an array of objects, and specify the slot name.

props:
  text:
  background:
children:
  - name: slot1
  - name: slot2