Customize Record Title

Hi, in ContractResource i have:

protected static ?string $recordTitleAttribute = 'id';

protected static ?string $recordTitleAttribute = 'id';

protected static ?string $recordTitleAttribute = 'id';

protected static ?string $recordTitleAttribute = 'id';

How can I customize the title so that I can see "View Contract No. [id]" or "Edit Contract No. [4]" ?