Meta label not showing

im trying to understand the meta labels in the default config for prometheus.
I got a basic setup with prometheus stack deployed with the helm chart on kubernetes.

When I create application from a deployment I see the label “container” in the service monitor.
But when its a pod created directly, I don’t see the label.

I discovered there is a lot of metadata like this one that get renamed to container:

  • __meta_kubernetes_pod_container_name

How are they added ? I dont see any of those labels on pods, deployments or replicaset.