This documentation is for XNAT versions 1.6.0 - 1.6.5. You can find the latest documentation for XNAT 1.7 at https://xnat.org/documentation
Creating subjects via the XNAT REST API is simple. Performing a PUT to the following URI would create a subject.
/data/archive/projects/TEST/subjects/1 (This would create a subject called '1' within the project 'TEST').
FYI, the project must exist before this command will succeed.
You can also assign demographics to this subject using the XML PATH shortcuts defined here.
To assign the gender and handedness to this subject, you would use the following PUT.
Review the list of XML PATH shortcuts for a comprehensive list of the available fields.