TFS is not supported for the server side VCS integration.
If you do local development just use the TFS client to version the assets of interest from the filesystem. For processes, tasks and rules you can install any eclipse plugin into Designer (I do not know if there is an eclipse plugin for TFS). If you use Designer workstation you can even version IS services from within Designer.
#webMethods#webMethods-General#Integration-Server-and-ESB