diff --git a/internal/types/types.go b/internal/types/types.go
index 41b538e61f..3ab8894c7c 100644
--- a/internal/types/types.go
+++ b/internal/types/types.go
@@ -569,6 +569,7 @@ type Proxy interface {
 	ReleaseDQLMessageStream(ctx context.Context, in *proxypb.ReleaseDQLMessageStreamRequest) (*commonpb.Status, error)
 }
 
+// ProxyComponent defines the interface of proxy component.
 type ProxyComponent interface {
 	Proxy