c0

In lua those keys have to be provided as a Type > String.

c0 can be used as a CharacterData > CharacterKey. It represents the most relevant CharacterData.
For example:
In character interactions it would be the character that is interacted with.

p0

p0 can be used as a PlaceData > PlaceKey. It represents the most relevant PlaceData.
For example:
When evaluating if a place is open it would be the place evaluated.

l0

l0 can be used as a LocationData > LocationKey. It represents the most relevant LocationData.
For example:
When evaluating if a location is open it would be the location evaluated.

i0

i0 can be used as a ItemData > ItemKey. It represents the most relevant ItemData.
For example:
When an item is used it would be the item used.