diff --git a/server/operation.go b/server/operation.go
index 3298b40..1c0a744 100644
--- a/server/operation.go
+++ b/server/operation.go
@@ -153,8 +153,8 @@ func marshal(argval reflect.Value, output map[string]string) map[string]string {
 			output[argval.Type().Field(i).Name] = fmt.Sprintf("%d", argval.Field(i).Int())
 		} else if argval.Field(i).Kind() == reflect.Array || argval.Field(i).Kind() == reflect.Slice {
 			var conv []string
-			for i := 0; i < argval.Field(i).Len(); i++ {
-				conv = append(conv, argval.Field(i).Index(i).String())
+			for j := 0; j < argval.Field(i).Len(); j++ {
+				conv = append(conv, argval.Field(i).Index(j).String())
 			}
 			output[argval.Type().Field(i).Name] = strings.Join(conv, "\n")
 		} else {