Value is not in the declared profile's set
A field the exchange documents has a closed value set, and this payload is outside it.
What it means
Under prebid-server, ext.prebid.trace must be verbose or basic; bid.ext.prebid.type must be banner, video, native, or audio; imp.ext.prebid.bidder must be an object keyed by bidder code; app.ext.prebid.source and version must be strings when present.
Why it matters
These are documented PBS extension contracts, not OpenRTB enums. A typo here is dropped or 400s depending on the field.
How to fix it
Use a documented value, or omit the field. Bidder param objects themselves are opaque and not schema-checked.
Example that trips it
{ "id": "req-1", "imp": [{ "id": "1", "banner": { "w": 300, "h": 250 }, "ext": { "prebid": { "bidder": { "appnexus": {} } } } }], "ext": { "prebid": { "trace": "debug" } } }Validated with --profile prebid-server. trace allows verbose and basic, not debug.
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.
Back to the full diagnostic code reference.