diff --git a/Library/Homebrew/requirements/xcode_requirement.rb b/Library/Homebrew/requirements/xcode_requirement.rb
index 974de5f67d..97e1dde8da 100644
--- a/Library/Homebrew/requirements/xcode_requirement.rb
+++ b/Library/Homebrew/requirements/xcode_requirement.rb
@@ -2,6 +2,9 @@
 
 require "requirement"
 
+# A requirement on Xcode.
+#
+# @api private
 class XcodeRequirement < Requirement
   fatal true