{
    "title": "carts",
    "type": "object",
    "properties": {
        "id": {
            "type": "integer",
            "description": "Primary key, auto-increment"
        },
        "user_id": {
            "type": "string",
            "description": "User id, system-managed"
        },
        "items_json": {
            "type": "string",
            "description": "JSON-encoded cart items"
        }
    },
    "required": [
        "id",
        "user_id"
    ]
}