diff --git a/clusters/noble/bootstrap/argocd/app-of-apps/kube-prometheus-application.yaml b/clusters/noble/bootstrap/argocd/app-of-apps/kube-prometheus-application.yaml
index bb8f5c0..ab70ee3 100644
--- a/clusters/noble/bootstrap/argocd/app-of-apps/kube-prometheus-application.yaml
+++ b/clusters/noble/bootstrap/argocd/app-of-apps/kube-prometheus-application.yaml
@@ -23,6 +23,9 @@ spec:
     server: https://kubernetes.default.svc
     namespace: monitoring
   # Manual sync: Ansible helm runs first; enable automation after cutover (see ../README.md §5).
+  # ServerSideApply: kube-prometheus-stack CRDs exceed the 256KiB **last-applied-configuration** limit
+  # when applied client-side (Argo/kubectl); SSA avoids that annotation.
   syncPolicy:
     syncOptions:
       - CreateNamespace=true
+      - ServerSideApply=true