The staff members can approve, delete, or mark comments as spam provided the team they belong to has the required permissions. The permissions to delete the comments can be assigned to the teams from Admin Control Panel.
This article provides steps involved in setting the staff's permission to moderate comments on knowledgebase articles.
To configure the permission:
Log in to your Kayako instance and go to the Admin Control Panel.
Click Staff, and then select Manage Teams.
Select the Team you want to manage by checking it.
Click the 'Permissions: Staff' tab and scroll down to the Base section.
In the Comments section, select the action (View, Update, or Delete) you want to grant.
Click the Update button to save the changes.