diff --git a/internal/util/indexparamcheck/conf_adapter.go b/internal/util/indexparamcheck/conf_adapter.go
index d64db33b95..6bb7a2d6c1 100644
--- a/internal/util/indexparamcheck/conf_adapter.go
+++ b/internal/util/indexparamcheck/conf_adapter.go
@@ -109,6 +109,7 @@ const (
 // METRICS is a set of all metrics types supported for float vector.
 var METRICS = []string{L2, IP} // const
 
+// BinIDMapMetrics is a set of all metric types supported for binary vector.
 var BinIDMapMetrics = []string{HAMMING, JACCARD, TANIMOTO, SUBSTRUCTURE, SUPERSTRUCTURE}   // const
 var BinIvfMetrics = []string{HAMMING, JACCARD, TANIMOTO}                                   // const
 var supportDimPerSubQuantizer = []int{32, 28, 24, 20, 16, 12, 10, 8, 6, 4, 3, 2, 1}        // const