diff --git a/internal/audit/repo.go b/internal/audit/repo.go
index 65eb011..f55af6b 100644
--- a/internal/audit/repo.go
+++ b/internal/audit/repo.go
@@ -102,6 +102,10 @@ func (r *Repo) List(ctx context.Context, limit int) ([]*Entry, error) {
 	if err := rows.Err(); err != nil {
 		return nil, fmt.Errorf("audit: rows: %w", err)
 	}
+	if out == nil {
+		// Force empty array (not null) in JSON.
+		out = []*Entry{}
+	}
 	return out, nil
 }
 
diff --git a/internal/storage/cluster_repo.go b/internal/storage/cluster_repo.go
index 721d58c..89b2bb8 100644
--- a/internal/storage/cluster_repo.go
+++ b/internal/storage/cluster_repo.go
@@ -118,6 +118,10 @@ func (r *ClusterRepo) List(ctx context.Context) ([]*cluster.Cluster, error) {
 	if err := rows.Err(); err != nil {
 		return nil, fmt.Errorf("storage: list clusters: %w", err)
 	}
+	if out == nil {
+		// Force empty array (not null) in JSON for LLM/front-end ergonomics.
+		out = []*cluster.Cluster{}
+	}
 	return out, nil
 }