things:feature.definition.empty

{
  "topic": "unknown/unknown/things/twin/errors",
  "headers": {},
  "path": "/",
  "value": {
    "status": 400,
    "error": "things:feature.definition.empty",
    "message": "Feature Definition must not be empty!",
    "description": "A Feature Definition must contain at least one element. It can however also be set to null or deleted completely."
  },
  "status": 400
}