diff --git a/config/routes.rb b/config/routes.rb
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -94,6 +94,7 @@
       get 'download'
       get 'compiler_msg'
       get 'rejudge'
+      get 'set_tag'
     end
     collection do
       get 'prob/:problem_id', to: 'submissions#index', as: 'problem'