It is a set of tools, part of the GeneXus Cloud Components of GeneXus Cloud Deployment Services.
It is installed right under you GeneXus installation to extend the latter's functionality. It lets you deploy using the IDE through the GeneXus Cloud Extension and also deploying batch through the GXcloud MSBuild Tasks.
It Is shipped built-in with GeneXus since GeneXus X Evolution 3 Upgrade 7 and GeneXus 15.
If you are using GeneXus X Evolution 3 Upgrade 6 or lower,
Anyway, GeneXus X Evolution 3 Upgrade 3 or higher is required.