diff --git a/output/cloud/v1/output.go b/output/cloud/v1/output.go
index fb80b5d20dba..a8554c0f3eb2 100644
--- a/output/cloud/v1/output.go
+++ b/output/cloud/v1/output.go
@@ -24,6 +24,9 @@ type Output struct {
 	logger logrus.FieldLogger
 	config cloudapi.Config
 
+	// referenceID is the legacy name used by the Backend for the test run id.
+	// Note: This output's version is almost deprecated so we don't apply
+	// the renaming to its internals.
 	referenceID string
 	client      *MetricsClient