{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "http://jsonlogic.com/schemas/operators/accessor/missing.json",

  "title": "missing",
  "description": "Takes an array of data keys to search for (same format as var). Returns an array of any keys that are missing from the data object, or an empty array.",
  "type": "object",
  "additionalProperties": false,
  "required": ["missing"],
  "properties": {
    "missing": {
      "$ref": "http://jsonlogic.com/schemas/common/var.json"
    }
  },
  "examples": [
    { "missing": ["a", "b"] },
    { "if": [
      { "missing": ["a", "b"] },
      "'a' and/or 'b' are missing",
      "OK to proceed"
    ]}
  ]
}