Manual:Hooks/SkinTemplateToolboxEnd

Can be used for adding items to the toolbox. This hook was deprecated in MW 1.35, and removed in MW 1.37. In its place, you can use either of the following hooks:
 * SkinBuildSidebar - respects caching; only called when a page is recreated
 * SidebarBeforeOutput - ignores caching; called on every page load

Details

 * $tpl: template reference