To add a filter of performance document in custom probation alert

Hi Team,

We have created a resource alert named Probation Alert which will trigger a notification if probation end date is in next 30 days.

We have scheduled eligibility batch process to create 'Probationary review document' for employee.

Is there any way to add a filter in the alert in order "to check the probationary review document is assigned or not "?

Any help on this would be appreciated!

Thanks,

Jahanavi