openrtb.request.tmax_implausible
What it means
tmax exceeds 10,000, which is ten seconds of auction budget. Real-time auctions complete in a few hundred milliseconds, so a value this size nearly always means the sender wrote seconds (or a whole timeout config) into a field defined as milliseconds.
Why it matters
Bidders either clamp the value to their own maximum or flag the request as malformed. An exchange whose requests carry impossible timeouts reads as an exchange whose other fields deserve suspicion too.
How to fix it
Express tmax in milliseconds. If your internal config keeps timeouts in seconds, convert at the serialization boundary and add a unit suffix to the config key so the next reader does not repeat the mistake.
Example that trips it
{ "tmax": 300000 }Five minutes. Someone sent seconds times a thousand, or a server timeout.
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.