diff --git a/Library/Homebrew/cask/lib/hbc/cli/internal_stanza.rb b/Library/Homebrew/cask/lib/hbc/cli/internal_stanza.rb
index bce5db3e1a..b5df67b0ff 100644
--- a/Library/Homebrew/cask/lib/hbc/cli/internal_stanza.rb
+++ b/Library/Homebrew/cask/lib/hbc/cli/internal_stanza.rb
@@ -45,7 +45,8 @@ module Hbc
         @format = :to_yaml if yaml?
 
         return if DSL::DSL_METHODS.include?(stanza)
-        raise ArgumentError, "Illegal stanza: '#{stanza}'"
+        raise ArgumentError,
+          "Unknown/unsupported stanza: '#{stanza}' Check cask reference for supported stanzas."
       end
 
       def run
@@ -72,7 +73,8 @@ module Hbc
 
           if value.nil? || (value.respond_to?(:to_a) && value.to_a.empty?) ||
              (value.respond_to?(:to_s) && value.to_s == "{}")
-            raise CaskError, "no such stanza '#{artifact_name ? artifact_name : stanza}' on Cask '#{cask}'"
+            stanza_name = artifact_name ? artifact_name : stanza
+            raise CaskError, "no such stanza '#{stanza_name}' on Cask '#{cask}'"
           end
 
           if format
diff --git a/Library/Homebrew/test/cask/cli/internal_stanza_spec.rb b/Library/Homebrew/test/cask/cli/internal_stanza_spec.rb
index 52bbf4ee0b..a020b33d49 100644
--- a/Library/Homebrew/test/cask/cli/internal_stanza_spec.rb
+++ b/Library/Homebrew/test/cask/cli/internal_stanza_spec.rb
@@ -6,10 +6,10 @@ describe Hbc::CLI::InternalStanza, :cask do
     }.to output("http://example.com/gpg-signature.asc\n").to_stdout
   end
 
-  it "raises an exception when stanza is invalid" do
+  it "raises an exception when stanza is unknown/unsupported" do
     expect {
-      described_class.new("invalid_stanza", "with-gpg")
-    }.to raise_error(/Illegal stanza/)
+      described_class.new("this_stanza_does_not_exist", "with-gpg")
+    }.to raise_error(/Unknown\/unsupported stanza/)
   end
 
   it "raises an exception when normal stanza is not present on cask" do
@@ -37,6 +37,6 @@ describe Hbc::CLI::InternalStanza, :cask do
     command = described_class.new("artifacts", "with-gpg")
     expect {
       command.run
-    }.to output("{:app=>[[\"Caffeine.app\"]]}\n").to_stdout
+    }.to output(/Caffeine\.app/).to_stdout
   end
 end