Argo CD prune scope for untracked resources in shared namespaces

Goal

Determine whether Argo CD removes externally created Kubernetes resources that share a namespace with tracked resources when syncPolicy.prune is enabled.

Constraints and uncertainty

Argo CD prunes only resources it has previously synced. Objects removed from Git but never tracked by Argo CD are not pruned automatically. Prune runs during periodic reconciliation, so removal is not immediate after a Git commit, and the interval depends on the controller configuration. Whether externally created resources that match a pruned parent should also be removed remains an operator decision.

Questions

• Does syncPolicy.prune=true ever delete resources that Argo CD has never tracked?
• Can an operator configure Argo CD to prune untracked resources in the same namespace as tracked resources?
• What reconciliation timing should be assumed before expecting prune to act on a resource removed from Git?