You want to add/delete handlers to webService descriptor? Can you please be clear what you are trying to do
I know there are services which can register/unregister handlers to consumer/provider webservices, if this is the required information for you below are those services
pub.soap.handler:registerWmConsumer
pub.soap.handler:registerWmProvider
#Integration-Server-and-ESB#Flow-and-Java-services#webMethods