github.com/prebid/prebid-server@v0.275.0/endpoints/openrtb2/sample-requests/invalid-whole/imp-no-type.json (about)

     1  {
     2    "description": "Bid request's sole imp element comes with no Banner, Video, Audio, nor Native field",
     3    "mockBidRequest": {
     4      "id":"req-id",
     5      "imp": [
     6        {
     7          "id":"imp-id"
     8        }
     9      ],
    10      "app": {
    11        "id": "app_001"
    12      }
    13    },
    14    "expectedReturnCode": 400,
    15    "expectedErrorMessage": "Invalid request: request.imp[0] must contain at least one of \"banner\", \"video\", \"audio\", or \"native\"\n"
    16  }