diff --git a/lib/awful/hotkeys_popup/keys/firefox.lua b/lib/awful/hotkeys_popup/keys/firefox.lua
index 5385db670..2c8aa6edd 100644
--- a/lib/awful/hotkeys_popup/keys/firefox.lua
+++ b/lib/awful/hotkeys_popup/keys/firefox.lua
@@ -1,3 +1,11 @@
+---------------------------------------------------------------------------
+--- Firefox hotkeys for awful.hotkeys_widget
+--
+-- @author Jonathan <jonathan@tinypulse.com>
+-- @copyright 2017 Jonathan
+-- @module awful.hotkeys_popup.keys.firefox
+---------------------------------------------------------------------------
+
 local hotkeys_popup = require("awful.hotkeys_popup.widget")
 local fire_rule = { class = { "Firefox" } }
 for group_name, group_data in pairs({
diff --git a/lib/awful/hotkeys_popup/widget.lua b/lib/awful/hotkeys_popup/widget.lua
index 5403219b8..79121dc7b 100644
--- a/lib/awful/hotkeys_popup/widget.lua
+++ b/lib/awful/hotkeys_popup/widget.lua
@@ -556,8 +556,8 @@ function widget.new(args)
     end
 
     --- Add hotkey group rules for third-party applications.
-    -- @tparam group hotkeys group name,
-    -- @tparam data rule data for the group
+    -- @tparam string group hotkeys group name,
+    -- @tparam table data rule data for the group
     -- see `awful.hotkeys_popup.key.vim` as an example.
     function widget_instance:add_group_rules(group, data)
         self.group_rules[group] = data
@@ -590,11 +590,11 @@ end
 
 --- Add hotkey group rules for third-party applications
 -- (default widget instance will be used).
--- @tparam string hotkeys group name,
--- @tparam table rule data for the group
+-- @tparam string group rule group name,
+-- @tparam table data rule data for the group
 -- see `awful.hotkeys_popup.key.vim` as an example.
-function widget.add_group_rules(...)
-    return get_default_widget():add_group_rules(...)
+function widget.add_group_rules(group, data)
+    return get_default_widget():add_group_rules(group, data)
 end
 
 return widget