diff --git a/Library/Homebrew/formulary.rb b/Library/Homebrew/formulary.rb
index c9e147a91ea69b8999ae3204e595fc427b893cd3..f71354f0895ae89ec2f77c63d3199e9e87cdf97e 100644
--- a/Library/Homebrew/formulary.rb
+++ b/Library/Homebrew/formulary.rb
@@ -6,7 +6,8 @@ require "tab"
 
 # The Formulary is responsible for creating instances of {Formula}.
 # It is not meant to be used directly from formulae.
-
+#
+# @api private
 module Formulary
   extend Cachable
 
@@ -150,7 +151,7 @@ module Formulary
     end
   end
 
-  # Loads formulae from bottles.
+  # Loads a formula from a bottle.
   class BottleLoader < FormulaLoader
     def initialize(bottle_name)
       case bottle_name
@@ -187,6 +188,7 @@ module Formulary
     end
   end
 
+  # Loads a formula from a path to an alias.
   class AliasLoader < FormulaLoader
     def initialize(alias_path)
       path = alias_path.resolved_path
@@ -298,6 +300,7 @@ module Formulary
     end
   end
 
+  # Pseudo-loader which will raise a `FormulaUnavailableError` when trying to load the corresponding formula.
   class NullLoader < FormulaLoader
     def initialize(name)
       super name, Formulary.core_path(name)