Unable to update ticket_attribute of type list via API

Hey there, I am currently building an intercom integration to sync tickets. I have a custom ticket attribute called “priority” of type list which has the options “urgent”, “high”, “normal”,  and “low”.

I try to update the ticket attribute like this via the Dev Docs and the try out button. Without the attribute the flow works fine (so my Bearer token and the rest is set up correctly):

Json body:

{
  "ticket_attributes": {
    "_default_title_": "example",
    "_default_description_": "there is a problem",
    "priority": "urgent"
  },
  "state": "in_progress"
}

I get the following error message:

{ "type": "error.list", "request_id": "0016erd0q33c1jgjf750","errors": [{ "code": "parameter_invalid", "message": "'urgent' is not a valid value for attribute 'priority' of type 'list'" } ] }

I also tried “priority”: [“urgent”], “priority”: “[urgent]” and more. Could you tell me which schema is expected for the list attribute?

Kind Regards

Ian