Then I looked for the REST API services to add tags (http:/myalfresco/alfresco/service/index/family/Tagging) but looking at URLs it seems that I will also need tags id.
So the problem for me is: How do I create new Tags into Alfresco from an external app (based on Java)?
The first thing I had in mind was to try to create tags manually via CMIS. That way I tried to get Tags Root (workspace://SpacesStore/tag:tag-root) to create new tags inside. But it has been impossible for me to cast that object (cm:category) to any CMIS Java objects (CmisObject, Document or Folder).
Via Rest I have not found any solution yet, so I am lost…