diff --git a/lib/valve.js b/lib/valve.js
index <HASH>..<HASH> 100644
--- a/lib/valve.js
+++ b/lib/valve.js
@@ -1103,7 +1103,8 @@ Chain.prototype.enumerated = function(map) {
       if (map.hasOwnProperty(value)) {
         callback(null, map[value]);
       } else {
-        callback("Invalid value '" + value + "'");
+        callback("Invalid value '" + value + "'. Should be one of " +
+                 "(" + Object.keys(map).join(', ') + ").");
       }
     },
     help: 'One of (' + Object.keys(map).join(', ') + ')'
@@ -1126,7 +1127,8 @@ Chain.prototype.inArray = function(array) {
       if (array.indexOf(value) !== -1) {
         callback(null, value);
       } else {
-        callback("Invalid value '" + value + "'");
+        callback("Invalid value '" + value + "'. Should be one of " +
+                 "(" + array.join(', ') + ").");
       }
     },
     help: 'One of (' + array.join(', ') + ')'
Better error messages for enum and inArray.