List custom pages

{
  "type": "object",
  "properties": {
    "account_id": {
      "type": "string",
      "description": "Identifier."
    },
    "page": {
      "type": "integer",
      "description": "Page number of results."
    },
    "per_page": {
      "type": "integer",
      "description": "Number of results per page."
    }
  },
  "required": [
    "account_id"
  ],
  "additionalProperties": false
}