diff --git a/.gitignore b/.gitignore
index 4a9215e..fca681e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,4 +2,5 @@
 pkg
 node_modules
 promptfoo-errors.log
-electron-eval/
\ No newline at end of file
+electron-eval/
+coverage/
\ No newline at end of file
diff --git a/Gemfile b/Gemfile
index bfe9595..807c45e 100644
--- a/Gemfile
+++ b/Gemfile
@@ -10,5 +10,6 @@ group :development, :test do
   gem 'rake', '~> 13.0'
   gem 'rspec', '~> 3.12'
   gem 'rubocop', '~> 1.73.2'
+  gem 'simplecov', '~> 0.22.0'
   gem 'webmock', '~> 3.18'
 end
diff --git a/Gemfile.lock b/Gemfile.lock
index 19fb9f5..61727e9 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -10,6 +10,7 @@ GEM
       bigdecimal
       rexml
     diff-lcs (1.6.0)
+    docile (1.4.1)
     hashdiff (1.1.2)
     json (2.10.1)
     language_server-protocol (3.17.0.4)
@@ -55,6 +56,12 @@ GEM
     rubocop-ast (1.38.1)
       parser (>= 3.3.1.0)
     ruby-progressbar (1.13.0)
+    simplecov (0.22.0)
+      docile (~> 1.1)
+      simplecov-html (~> 0.11)
+      simplecov_json_formatter (~> 0.1)
+    simplecov-html (0.13.2)
+    simplecov_json_formatter (0.1.4)
     unicode-display_width (3.1.4)
       unicode-emoji (~> 4.0, >= 4.0.4)
     unicode-emoji (4.0.4)
@@ -73,6 +80,7 @@ DEPENDENCIES
   rake (~> 13.0)
   rspec (~> 3.12)
   rubocop (~> 1.73.2)
+  simplecov (~> 0.22.0)
   webmock (~> 3.18)
 
 BUNDLED WITH
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 3020700..4bea86f 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,5 +1,11 @@
 # frozen_string_literal: true
 
+require 'simplecov'
+SimpleCov.start do
+  add_filter '/spec/'
+  add_filter '/vendor/'
+end
+
 require 'bundler/setup'
 require 'webmock/rspec'
 require 'pry'