json_schema: {
      "$schema": "http://json-schema.org/draft-04/schema#",
      "title": "HealthDescriptor",
      "description": "Health for an instance",
      "type": "object",
      "additionalProperties": false,
      "properties": {
          "srvcId": {
              "description": "Service ID, normally same as Module ID",
              "type": "string"
          },
          "instId": {
              "description": "Instance ID, unique on node",
              "type": "string"
          },
          "healthMessage": {
              "description": "Health message",
              "type": "string"
          },
          "healthStatus": {
              "description": "Whether healthy",
              "type": "boolean"
          }
      },
      "required": [
          "srvcId",
          "instId",
          "healthMessage",
          "healthStatus"
      ]
  }