diff --git a/jdr/type.go b/jdr/type.go
index b4de5a3..f328a1a 100644
--- a/jdr/type.go
+++ b/jdr/type.go
@@ -3,6 +3,7 @@ package jdr
 import(
     "html/template"
 
+    "fmt"
     "log"
     "errors"
     "strings"
@@ -91,7 +92,7 @@ func (self *VariableType_int) ToInt(value JsonValue) (int64, error) {
         if isInt {
             val = int64(val2)
         } else {
-            return 0, errors.New("Not int"))
+            return 0, errors.New("Bad int type: " + fmt.Sprintf("%T", value))
         }
     }