diff --git a/internal/distributed/querycoord/service.go b/internal/distributed/querycoord/service.go
index d56538d8d3..08279df534 100644
--- a/internal/distributed/querycoord/service.go
+++ b/internal/distributed/querycoord/service.go
@@ -238,6 +238,7 @@ func (s *Server) Stop() error {
 	return err
 }
 
+// SetRootCoord sets the RootCoord's client for QueryCoord component.
 func (s *Server) SetRootCoord(m types.RootCoord) error {
 	s.queryCoord.SetRootCoord(m)
 	return nil