diff --git a/Gemfile b/Gemfile
index 5332a42..df36eda 100644
--- a/Gemfile
+++ b/Gemfile
@@ -11,4 +11,5 @@ group :development, :test do
   gem 'rubocop'
   gem 'rubocop-rake'
   gem 'rubocop-rspec'
+  gem 'yard'
 end
diff --git a/Gemfile.lock b/Gemfile.lock
index 0ff2b98..2e2f3d8 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -50,6 +50,7 @@ GEM
       rubocop (~> 1.61)
     ruby-progressbar (1.13.0)
     unicode-display_width (2.6.0)
+    yard (0.9.37)
 
 PLATFORMS
   ruby
@@ -61,6 +62,7 @@ DEPENDENCIES
   rubocop-eightyfourcodes!
   rubocop-rake
   rubocop-rspec
+  yard
 
 BUNDLED WITH
    2.5.22