Workflow interaction with OAF page

We've had a request to remove a button from an OAF page.  Our developer says that the buttons on the page are dynamically created and they are being created based on results expected from the workflow.  I'm trying to determine at what point in the workflow it's calling out to build the OAF page and telling the page what results it will be expecting.  So if the workflow results from this piece could be accept, reject, request information...I'm trying to determine how workflow is communicating this information in order to build the OAF page.  The specific workflow I'm speaking of