diff --git a/pkg/redskyapi/experiments/v1alpha1/experiment.go b/pkg/redskyapi/experiments/v1alpha1/experiment.go
index 56d91d5..6ecdfa6 100644
--- a/pkg/redskyapi/experiments/v1alpha1/experiment.go
+++ b/pkg/redskyapi/experiments/v1alpha1/experiment.go
@@ -52,6 +52,8 @@ type Metric struct {
 	Name string `json:"name"`
 	// The flag indicating this metric should be minimized.
 	Minimize bool `json:"minimize,omitempty"`
+	// The flag indicating this metric is not optimized.
+	CollectOnly bool `json:"collectOnly,omitempty"`
 }
 
 type ConstraintType string