There are a couple of places where you'd need to start looking in order to get this working for your customized install, and you need to be a little familiar with Eclipse plugin development and extension points. I'd like to point you to https://github.com/SpringSource/ecli...ration-commons where we host our code for automatic workspace configuration, and also https://github.com/SpringSource/ecli...ation-tcserver where we host our tc Server integration (and where you'd get some example of automatic server configuration).
At the eclipse-integration-commons repository, the plugin org.springsource.ide.eclipse.commons.configurator exposes a few extension points, but the one you'd be interested in is the com.springsource.sts.ide.configurator.serverConfig urations. This extension tells STS that you have a server that you want auto-configured, where to find it, how to define it, etc. If you look into the tcserver git repository, the com.vmware.vfabric.ide.eclipse.tcserver.core plugin.xml contains about 6 examples of this extension point, so you can see how we've done if for tc Server.
In your case you'd need to include a custom Eclipse plugin in your STS. Your plugin would have a dependency to our org.springsource.ide.eclipse.commons.configurator plugin, and it would implement the com.springsource.sts.ide.configurator.serverConfig urations in a similar way that the tc Server integration does.
Hope this helps.
Leo Dos Santos
Committer, SpringSource Tool Suite