Cannot add platform osx (even though it is available)

MacBook-Pro-2:workspacemobile mp4$ cordova create test
Creating a new cordova project.
MacBook-Pro-2:workspacemobile mp4$ cd test
MacBook-Pro-2:test mp4$ cordova platform add osx

Error: Failed to fetch platform osx
Probably this is either a connection problem, or platform spec is incorrect.
Check your connection and platform name/version/URL.
Error: No compatible version found: cordova-osx@'>=4.0.0 <4.1.0'
Valid install targets:
["3.4.1"]