json_schema: {
    "properties": {
      "person1": {
        "properties": {
          "birthdate": {
            "description": "The birthdate of the first person in YYYY-MM-DD format",
            "format": "date",
            "type": "string"
          }
        },
        "required": [
          "birthdate"
        ],
        "type": "object"
      },
      "person2": {
        "properties": {
          "birthdate": {
            "description": "The birthdate of the second person in YYYY-MM-DD format",
            "format": "date",
            "type": "string"
          }
        },
        "required": [
          "birthdate"
        ],
        "type": "object"
      }
    },
    "required": [
      "person1",
      "person2"
    ],
    "type": "object"
  }