Prebid Server Imp names no bidder
The Prebid Server profile was declared, and this Imp has no bidder targeting and no stored request that would supply it after merge.
What it means
Prebid Server offers an impression to a bidder only when imp.ext.prebid.bidder.{bidder} is present (recommended), or the legacy imp.ext.{bidder} object, or a stored request / stored auction response id that PBS merges in. Reserved ext keys (prebid, data, skadn, gpid, tid, ae, igs, context, general, all) are not bidders. PBS returns 400: request.imp[0].ext must contain at least one bidder.
Why it matters
Without a bidder code, PBS has no adapter to call. The auction endpoint refuses the request rather than running an empty auction.
How to fix it
Put bidder params at imp.ext.prebid.bidder.{code}, or set imp.ext.prebid.storedrequest.id (or a top-level ext.prebid.storedrequest.id) if the stored request supplies them. Drop --profile prebid-server if this is not a PBS auction payload.
Example that trips it
{ "id": "req-1", "imp": [{ "id": "1", "banner": { "w": 300, "h": 250 } }] }Validated with --profile prebid-server. The same payload is valid against the specification.
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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