MediaWiki:Gwtoolset-reverse-creator-explanation/en

Sometimes the creator value is listed as "last name, first name" in the metadata. Checking this box will reverse that order and remove the comma, e.g., "da Vinci, Leonardo" would become "Leonardo da Vinci". Note that this relies on a single comma in the value; if there is no comma in the value, no change will be made, and if there is more than one comma, the change will only be made using the first comma.