Updating base Contribution Summary for build result

hi,
when doing teamAccept ant task with snapshotName argument the build result for the build has those values in Contribution Summary section of build result:
- Changes
- Repository Workspace
- Snapshot

When I try to do teamAccept without the snapshotName argument those values are not there.

There are no such ant tasks available in the docs. How can I add this data manually by parts?
I would like to add Changes & Workspace after teamAccept but associate a Snapshot with the build only if the build was successful.

I tried doing it using RTC Java API but I cannot access simple contributions (I can add artifacts, logs, etc.) as they are not available in public API (at least not in IBuildResultContribution - should I look in some other place?).
Does anyone know how to access base Contributions using RTC SDK?

Thanks,
Jakub