diff --git a/lib/capybara/server.rb b/lib/capybara/server.rb
index ee57f5c5..c9193d07 100644
--- a/lib/capybara/server.rb
+++ b/lib/capybara/server.rb
@@ -8,6 +8,7 @@ require 'capybara/server/animation_disabler'
 require 'capybara/server/checker'
 
 module Capybara
+  # @api private
   class Server
     class << self
       def ports