This paper presents a tool for verifying dynamic properties using the B formal method. For example, in a library system, typical dynamic properties would be that a member has a possibility to borrow a book or make a reservation if it is already reserved by another member. Starting from a B specification and a dynamic property, this tool generates the proof obligations that permit the user to check whether the property is verified on the B specification. The goal of such a tool is to discharge the users from tedious and error-prone activities