diff --git a/internal/util/indexparamcheck/conf_adapter.go b/internal/util/indexparamcheck/conf_adapter.go
index 2e696c8d50..9c1e2c4e2e 100644
--- a/internal/util/indexparamcheck/conf_adapter.go
+++ b/internal/util/indexparamcheck/conf_adapter.go
@@ -93,6 +93,7 @@ var supportDimPerSubQuantizer = []int{32, 28, 24, 20, 16, 12, 10, 8, 6, 4, 3, 2,
 var supportSubQuantizer = []int{96, 64, 56, 48, 40, 32, 28, 24, 20, 16, 12, 8, 4, 3, 2, 1} // const
 
 type ConfAdapter interface {
+    // CheckTrain returns true if the index can be built with the spcecific index parameters.
 	CheckTrain(map[string]string) bool
 }