Native response asset subtype does not match the request

openrtb.native.asset.type_mismatcherrorRequest/response pair

The response filled a request title slot with an image, or the other way around.

What it means

Each request asset asks for exactly one of title, img, video, or data. The response asset with that id must use the same subtype.

Why it matters

A title slot that receives an image URL does not render. Native templates are typed per asset id.

How to fix it

Return title.text for a title asset, img.url for an image asset, video.vasttag for video, data.value for data.

Example that trips it

{ "request": { "native": { "request": "{\"assets\":[{\"id\":1,\"title\":{\"len\":90}}]}" } }, "adm": "{\"link\":{\"url\":\"https://ex\"},\"assets\":[{\"id\":1,\"img\":{\"url\":\"https://cdn/x.png\"}}]}" }

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.

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