diff --git a/internal/indexnode/errors.go b/internal/indexnode/errors.go
index 986762e094..33f6f27434 100644
--- a/internal/indexnode/errors.go
+++ b/internal/indexnode/errors.go
@@ -21,6 +21,7 @@ import (
 	"fmt"
 )
 
+// msgIndexNodeIsUnhealthy return a message tha IndexNode is not healthy.
 func msgIndexNodeIsUnhealthy(nodeID UniqueID) string {
 	return fmt.Sprintf("index node %d is not ready", nodeID)
 }