diff --git a/Rakefile b/Rakefile
index 5a7afab..5d512c8 100644
--- a/Rakefile
+++ b/Rakefile
@@ -7,11 +7,4 @@ Rake::TestTask.new(:test) do |t|
   t.test_files = FileList["test/**/test_*.rb"]
 end
 
-task :sync_tool do
-  require 'fileutils'
-  FileUtils.cp "../ruby/tool/lib/core_assertions.rb", "./test/lib"
-  FileUtils.cp "../ruby/tool/lib/envutil.rb", "./test/lib"
-  FileUtils.cp "../ruby/tool/lib/find_executable.rb", "./test/lib"
-end
-
 task :default => :test