RTC Category modify name with api
One answer
ICategory tempCategory = null;
// Check category on RTC.
tempCategory = HBCategory.GetICategoryFromNamePath(teamRepository, projectArea, oldCategoryPathArray);
if(tempCategory != null){
tempCategory = (ICategory) tempCategory.getWorkingCopy();
tempCategory.setName(newCategoryName);
tempCategory = workItemClient.saveCategory(tempCategory, null);
}