Apparatus and method to coordinate requests provided to a data storage and retrieval system

A method to coordinate requests submitted to a data storage and retrieval system from one or more operator input stations, whereby an initialization request comprising a requested operation is provided at a first time to the data storage and retrieval system. At that first time the method provides a current history of previously-submitted commands to perform the requested operation. The method also generates a request history token at that first time. The first history is displayed to the user. The user then determines if the current history includes the requested operation. If the first history does not include the requested operation, the user at a second time submits a command to perform the requested operation. The method generates at that second time a current history token, and determines if the current history token matches the request history token. If the current history token matches the request history token, then the method performs the requested operation.