CumulusGuard in it's
onRun method push to page two variables:
cluster which contains current cluster's slug
clusterData which contains array of the current cluster data.
Since version 1.1.13 active cluster slug is also pushed to session and cookie as
cumulus_clusterslug by CumulusGuard component, but by design the cluster was designed to be get using url param.
What is more if you want to get current cluster's data somewhere in your code, then you may like the method from
$clusterSlug = $this->property('clusterSlug');
$clusterRepository = new ClusterRepository($clusterSlug);
$clusterData = $clusterRepository->getCurrentCluster();