diff --git a/internal/proxy/impl.go b/internal/proxy/impl.go
index 63ae42b5fb23c27f640d07618727dc5251a54527..f57b556cc5f2f4d9abd1030a39be69db6627adbb 100644
--- a/internal/proxy/impl.go
+++ b/internal/proxy/impl.go
@@ -1832,6 +1832,7 @@ func (node *Proxy) AlterAlias(ctx context.Context, request *milvuspb.AlterAliasR
 	return aat.result, nil
 }
 
+// CalcDistance calculates the distances between vectors.
 func (node *Proxy) CalcDistance(ctx context.Context, request *milvuspb.CalcDistanceRequest) (*milvuspb.CalcDistanceResults, error) {
 	param, _ := funcutil.GetAttrByKeyFromRepeatedKV("metric", request.GetParams())
 	metric, err := distance.ValidateMetricType(param)