What specific work does the patent agent mainly do? Be specific, please.

According to the regulations, patent agents mainly write patent application documents for the applicant, reply to the examiner's opinions, pay fees, collect and transmit all kinds of notices from the patent office on behalf of the applicant, handle all kinds of related procedures, review and invalidation. Simply put, it is to help the applicant to handle all matters related to the patent application. Of course, there is a charge.