What are the preconditions and the format of the XML file that PT accepts for XML imports?

The artifact types referenced by contents of the XML file should be added (ahead of the import) to the target project. If the attributes present in the XML file are not present in the artifact type, the import takes place with warnings. The XML definition file can be accessed here: https://<Domain Name>/dtd/pt.dtd, which defines the format of a well formed XML file in order to have it imported into PT.