I want command similar to az group exists, but for SQL server.

Currently use az sql server show, but it prints red exception into log which I don't want
Maybe az sql server list with JMES should do the trick, but I can't get it working.
E.g. az sql server list --query [?.name==mytestsqlsrv1234] gives
az sql server list: error: argument --query: invalid jmespath_type value: '[?.name==mytestsqlsrv1234]'