{
  "$schema": "https://json-structure.org/draft/2020-12/schema",
  "name": "Observation",
  "type": "object",
  "properties": {
    "date": {
      "type": "string"
    },
    "value": {
      "type": "['number', 'null']"
    },
    "status": {
      "type": "string"
    }
  }
}