Vungle VAST markup must start its VAST element within the first 100 bytes.

What it means

Vungle VAST markup must start its VAST element within the first 100 bytes. This check applies to the selected vendor contract and integration direction.

Why it matters

The declared profile checks the published partner contract alongside canonical OpenRTB. It does not verify runtime approval or account configuration.

How to fix it

Use the documented field type, value and representation at the reported path for this integration direction.

Example that trips it

{
  "id": "vungle-request",
  "seatbid": [
    {
      "bid": [
        {
          "id": "buyer-bid",
          "impid": "1",
          "price": 1,
          "adm": "                                                                                                    <VAST version=\"3.0\"><Ad/></VAST>",
          "adomain": [
            "advertiser.example"
          ]
        }
      ]
    }
  ]
}

Profile vungle, OpenRTB 2.5. The fixture asserts openrtb.profile.vungle.vast_prefix at seatbid[0].bid[0].adm.

Check your payload

Paste a bid request or response into the tester to see whether this code fires against it, or gate on the id in CI with the CLI: the id is stable, wording is not.

• Primary protocol documentation
• Replayable source fixture

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