@openstreetmap/id-tagging-schema/data/fields/capacity/caravans.json

The OpenStreetMap tagging model used by the iD editor

{
    "key": "capacity:caravans",
    "type": "number",
    "minValue": 0,
    "label": "Capacity (Campervan / Camping Trailer)",
    "placeholder": "10, 20, 50...",
    "prerequisiteTag": {
        "key": "caravans",
        "valueNot": "no"
    }
}