Unexpected request info description after OpenAPI import

I just imported an OpenAPI document with several requests. I noticed that the request info shows the description field as expected but also the text [object Object]. See attached image.

Where does this text come from?

The relevant part of the OpenAPI document.

  "paths": {
    "/klanten": {
      "get": {
        "description": "Lijst van klanten",
        "parameters": [ ... ],
        "responses": { ... }
      }
    },