{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "title": "SystemStats",
  "type": "object",
  "description": "Aggregate statistics about registered systems.",
  "properties": {
    "total": {
      "type": "integer",
      "description": "The total number of registered systems."
    },
    "stale": {
      "type": "integer",
      "description": "The number of stale systems."
    },
    "with_hits": {
      "type": "integer",
      "description": "Systems with at least one active recommendation."
    }
  }
}