{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "additionalProperties": false,
  "required": [
    "offer_id"
  ],
  "properties": {
    "offer_id": {
      "type": "hash",
      "description": "the id we use to identify this offer"
    }
  }
}