diff --git a/tasks/mrbgem_spec.rake b/tasks/mrbgem_spec.rake
index 224e69e9d..5b01bc79b 100644
--- a/tasks/mrbgem_spec.rake
+++ b/tasks/mrbgem_spec.rake
@@ -17,6 +17,9 @@ module MRuby
       alias mruby build
       attr_accessor :build_config_initializer
 
+      attr_accessor :version
+      attr_accessor :description, :summary
+      attr_accessor :homepage
       attr_accessor :licenses, :authors
       alias :license= :licenses=
       alias :author= :authors=