This appears to be a tracking task, not a completable project. Per https://www.mediawiki.org/wiki/Phabricator/Project_management/Tracking_tasks , tracking tasks should not be used. I think these tasks should be put in the MediaWiki-REST-API project.
If it is meant to be the umbrella for work planned for CPT for some time period, I think a project is the right way to indicate that also. But the project name should specify the scope.
@tstarling we are using initiative tasks as higher level Epic tasks - and perhaps should mark them as Epic. They group several Epic tasks into a multi-sprint initiative, but are not as heavy weight as a project. These tasks help to see the entire task tree for the initiative, which we would not be able to do from a Phabricator project. It might help clarify this point in this case if we rename this task (@eprodromou) to be more specific to what the initiative aims to accomplish, rather than scoping all of the core REST API, which does indeed seems more like a long term project.