diff --git a/CLAUDE.md b/CLAUDE.md
index 11db572..c20aac1 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -32,7 +32,10 @@ bundle exec rubocop      # Run RuboCop linter (uses rubocop-rails-omakase)
 
 ### Icon Management
 ```bash
-rake move_to_assets      # Move icons from tmp/heroicons to app/assets/images/icons/
+rake move_to_assets           # Move icons from tmp/heroicons to app/assets/images/icons/
+rake heroicons:sync           # Sync icons: copy used icons, remove unused ones
+rake heroicons:dry_run        # Preview what would be synced (dry run)
+rake heroicons:list_used      # List all icons currently used in the application
 ```
 
 ### Gem Development
@@ -60,4 +63,48 @@ The gem is designed to be included in Rails applications via:
 - Icons are organized by type (outline/solid/mini/micro) corresponding to different sizes and styles from Heroicons
 - The `icon_tag` helper defaults to `:outline` type and `"w-6 h-6"` classes
 - Icon lookup first checks the Rails app's assets, then falls back to the gem's assets
-- The `move_to_assets` rake task syncs icons from the upstream Heroicons repository
\ No newline at end of file
+- The `move_to_assets` rake task syncs icons from the upstream Heroicons repository
+
+## Automatic Icon Management
+
+The gem includes an intelligent icon management system that automatically manages which icons are included in your Rails application's assets:
+
+### How It Works
+
+1. **IconScanner**: Scans your Rails application code (views, helpers, components, controllers) for `icon_tag` usage
+2. **IconSyncer**: Copies only the used icons from the gem to your app's `app/assets/images/icons/` directory and removes unused ones
+
+### Usage in Host Applications
+
+**Manual Sync** (recommended workflow):
+```bash
+# Preview what would change
+rake heroicons:sync
+
+# List all icons currently used
+rake heroicons:list_used
+
+# Preview sync without making changes
+rake heroicons:dry_run
+```
+
+**Auto-sync on Asset Precompilation** (optional):
+```ruby
+# config/application.rb
+config.heroicons.auto_sync = true  # Auto-sync before assets:precompile
+```
+
+### Benefits
+
+- **Smaller asset size**: Only includes icons you actually use
+- **Clean assets directory**: Automatically removes icons when you stop using them
+- **Version control friendly**: Your app only commits the icons it needs
+- **Easy auditing**: Use `rake heroicons:list_used` to see all icons in use
+
+### Technical Details
+
+- **IconScanner** (`lib/heroicons/icon_scanner.rb`): Searches for `icon_tag` calls using regex patterns
+- **IconSyncer** (`lib/heroicons/icon_syncer.rb`): Manages copying/removing icon files
+- **Rake Tasks** (`lib/tasks/heroicons.rake`): Provides CLI commands for icon management
+- Supports all icon name formats: symbols, strings, underscored, and dashed names
+- Automatically normalizes underscored names to dashed format for file lookup
\ No newline at end of file
diff --git a/Gemfile.lock b/Gemfile.lock
index ee8d979..fae9d81 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,8 +1,13 @@
-GIT
-  remote: https://github.com/rails/rails.git
-  revision: c72f6713a427851a20a46c00c8ef3ab689d5bd32
-  branch: main
+PATH
+  remote: .
   specs:
+    heroicons-rails (0.4.1)
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    action_text-trix (2.1.15)
+      railties
     actioncable (8.1.0.beta1)
       actionpack (= 8.1.0.beta1)
       activesupport (= 8.1.0.beta1)
@@ -75,40 +80,6 @@ GIT
       securerandom (>= 0.3)
       tzinfo (~> 2.0, >= 2.0.5)
       uri (>= 0.13.1)
-    rails (8.1.0.beta1)
-      actioncable (= 8.1.0.beta1)
-      actionmailbox (= 8.1.0.beta1)
-      actionmailer (= 8.1.0.beta1)
-      actionpack (= 8.1.0.beta1)
-      actiontext (= 8.1.0.beta1)
-      actionview (= 8.1.0.beta1)
-      activejob (= 8.1.0.beta1)
-      activemodel (= 8.1.0.beta1)
-      activerecord (= 8.1.0.beta1)
-      activestorage (= 8.1.0.beta1)
-      activesupport (= 8.1.0.beta1)
-      bundler (>= 1.15.0)
-      railties (= 8.1.0.beta1)
-    railties (8.1.0.beta1)
-      actionpack (= 8.1.0.beta1)
-      activesupport (= 8.1.0.beta1)
-      irb (~> 1.13)
-      rackup (>= 1.0.0)
-      rake (>= 12.2)
-      thor (~> 1.0, >= 1.2.2)
-      tsort (>= 0.2)
-      zeitwerk (~> 2.6)
-
-PATH
-  remote: .
-  specs:
-    heroicons-rails (0.4.1)
-
-GEM
-  remote: https://rubygems.org/
-  specs:
-    action_text-trix (2.1.15)
-      railties
     ast (2.4.3)
     base64 (0.3.0)
     benchmark (0.4.1)
@@ -193,6 +164,20 @@ GEM
       rack (>= 1.3)
     rackup (2.2.1)
       rack (>= 3)
+    rails (8.1.0.beta1)
+      actioncable (= 8.1.0.beta1)
+      actionmailbox (= 8.1.0.beta1)
+      actionmailer (= 8.1.0.beta1)
+      actionpack (= 8.1.0.beta1)
+      actiontext (= 8.1.0.beta1)
+      actionview (= 8.1.0.beta1)
+      activejob (= 8.1.0.beta1)
+      activemodel (= 8.1.0.beta1)
+      activerecord (= 8.1.0.beta1)
+      activestorage (= 8.1.0.beta1)
+      activesupport (= 8.1.0.beta1)
+      bundler (>= 1.15.0)
+      railties (= 8.1.0.beta1)
     rails-dom-testing (2.3.0)
       activesupport (>= 5.0.0)
       minitest
@@ -200,6 +185,15 @@ GEM
     rails-html-sanitizer (1.6.2)
       loofah (~> 2.21)
       nokogiri (>= 1.15.7, != 1.16.7, != 1.16.6, != 1.16.5, != 1.16.4, != 1.16.3, != 1.16.2, != 1.16.1, != 1.16.0.rc1, != 1.16.0)
+    railties (8.1.0.beta1)
+      actionpack (= 8.1.0.beta1)
+      activesupport (= 8.1.0.beta1)
+      irb (~> 1.13)
+      rackup (>= 1.0.0)
+      rake (>= 12.2)
+      thor (~> 1.0, >= 1.2.2)
+      tsort (>= 0.2)
+      zeitwerk (~> 2.6)
     rainbow (3.1.1)
     rake (13.3.0)
     rbs (3.9.4)
@@ -283,7 +277,7 @@ PLATFORMS
 DEPENDENCIES
   heroicons-rails!
   puma
-  rails!
+  rails
   rubocop-rails-omakase
   ruby-lsp
   sqlite3
diff --git a/README.md b/README.md
index d44034a..990ddec 100644
--- a/README.md
+++ b/README.md
@@ -38,6 +38,50 @@ app/assets/images/icons/custom/
 <%= icon_tag "custom-arrow", type: :custom, class: "w-4 h-4" %>
 ```
 
+## Icon Management
+
+The gem includes intelligent icon management that keeps your assets directory clean and optimized:
+
+### Automatic Icon Syncing
+
+Only include icons you actually use in your application's assets:
+
+```bash
+# Scan your app and sync icons (copies used icons, removes unused ones)
+$ rake heroicons:sync
+
+# Preview what would be synced without making changes
+$ rake heroicons:dry_run
+
+# List all icons currently used in your application
+$ rake heroicons:list_used
+```
+
+### How It Works
+
+1. The scanner searches your Rails app for `icon_tag` usage in views, helpers, and components
+2. Only the icons you're actually using are copied to `app/assets/images/icons/`
+3. Icons you've removed from your code are automatically deleted from assets
+4. Your repository stays clean with only the icons you need
+
+### Benefits
+
+- **Smaller asset bundles**: Only includes icons you use
+- **Automatic cleanup**: Removes unused icons automatically
+- **Easy auditing**: See exactly which icons your app uses
+- **Version control friendly**: Only commit icons you actually need
+
+### Optional Auto-sync
+
+Enable automatic syncing before asset precompilation:
+
+```ruby
+# config/application.rb
+config.heroicons.auto_sync = true
+```
+
+When enabled, icons will be automatically synced before `rake assets:precompile` runs.
+
 ## Installation
 Add this line to your application's Gemfile:
 
diff --git a/lib/heroicons-rails.rb b/lib/heroicons-rails.rb
index 45f0370..762da32 100644
--- a/lib/heroicons-rails.rb
+++ b/lib/heroicons-rails.rb
@@ -1,6 +1,8 @@
 require_relative "heroicons/version"
 require_relative "heroicons/engine"
 require_relative "heroicons/errors"
+require_relative "heroicons/icon_scanner"
+require_relative "heroicons/icon_syncer"
 
 module Heroicons
   def self.root
diff --git a/lib/heroicons/engine.rb b/lib/heroicons/engine.rb
index df8b947..bde90a7 100644
--- a/lib/heroicons/engine.rb
+++ b/lib/heroicons/engine.rb
@@ -2,10 +2,26 @@ module Heroicons
   class Engine < ::Rails::Engine
     isolate_namespace Heroicons
 
+    # Configuration options
+    config.heroicons = ActiveSupport::OrderedOptions.new
+    config.heroicons.auto_sync = false # Set to true to auto-sync icons before asset compilation
+
+    # Load rake tasks
+    rake_tasks do
+      load File.expand_path("../tasks/heroicons.rake", __dir__)
+    end
+
     config.to_prepare do
       ActiveSupport.on_load(:action_view) do
         include Heroicons::ApplicationHelper
       end
     end
+
+    # Auto-sync icons before asset precompilation if enabled
+    config.before_initialize do |app|
+      if app.config.heroicons.auto_sync && defined?(Rake) && Rake::Task.task_defined?("assets:precompile")
+        Rake::Task["assets:precompile"].enhance(["heroicons:sync"])
+      end
+    end
   end
 end
diff --git a/lib/heroicons/icon_scanner.rb b/lib/heroicons/icon_scanner.rb
new file mode 100644
index 0000000..0d37746
--- /dev/null
+++ b/lib/heroicons/icon_scanner.rb
@@ -0,0 +1,62 @@
+module Heroicons
+  # Scans Rails application for icon_tag usage to determine which icons are being used
+  class IconScanner
+    # Matches: icon_tag(:name), icon_tag("name"), icon_tag :name, icon_tag "name"
+    # Also captures type parameter if present: type: :solid
+    ICON_TAG_PATTERN = /icon_tag\s*\(?\s*[:"']([a-z_-]+)["']?\s*(?:,\s*type:\s*:([a-z]+))?\)?/i
+    SEARCHABLE_EXTENSIONS = %w[.erb .haml .slim .rb].freeze
+
+    attr_reader :rails_root
+
+    def initialize(rails_root = Rails.root)
+      @rails_root = rails_root
+    end
+
+    # Returns a hash of used icons grouped by type
+    # Example: { outline: ['x-mark', 'home'], solid: ['check'], mini: ['star'] }
+    def scan_used_icons
+      used_icons = Hash.new { |h, k| h[k] = Set.new }
+
+      searchable_files.each do |file_path|
+        content = File.read(file_path)
+        extract_icons_from_content(content, used_icons)
+      end
+
+      # Convert sets to sorted arrays
+      used_icons.transform_values { |set| set.to_a.sort }
+    rescue => e
+      Rails.logger&.error("[Heroicons] Error scanning for icons: #{e.message}")
+      {}
+    end
+
+    private
+
+    def searchable_files
+      search_paths = [
+        File.join(rails_root, "app/views/**/*"),
+        File.join(rails_root, "app/helpers/**/*"),
+        File.join(rails_root, "app/components/**/*"),
+        File.join(rails_root, "app/controllers/**/*")
+      ]
+
+      search_paths.flat_map do |pattern|
+        Dir.glob(pattern).select do |path|
+          File.file?(path) && SEARCHABLE_EXTENSIONS.any? { |ext| path.end_with?(ext) }
+        end
+      end
+    end
+
+    def extract_icons_from_content(content, used_icons)
+      content.scan(ICON_TAG_PATTERN) do |match|
+        icon_name = match[0]&.strip
+        icon_type = match[1]&.strip&.to_sym || :outline
+
+        next unless icon_name
+
+        # Normalize icon name: convert underscores to dashes
+        normalized_name = icon_name.tr("_", "-")
+        used_icons[icon_type] << normalized_name
+      end
+    end
+  end
+end
diff --git a/lib/heroicons/icon_syncer.rb b/lib/heroicons/icon_syncer.rb
new file mode 100644
index 0000000..f748dab
--- /dev/null
+++ b/lib/heroicons/icon_syncer.rb
@@ -0,0 +1,141 @@
+require "fileutils"
+
+module Heroicons
+  # Syncs icons from gem to Rails app assets based on usage
+  # Copies only used icons and removes unused ones
+  class IconSyncer
+    ICON_TYPES = %i[outline solid mini micro].freeze
+
+    attr_reader :rails_root, :scanner
+
+    def initialize(rails_root = Rails.root, scanner: nil)
+      @rails_root = rails_root
+      @scanner = scanner || IconScanner.new(rails_root)
+    end
+
+    # Syncs icons: copies used ones from gem, removes unused ones from app
+    # Returns stats hash with copied, removed, and kept counts
+    def sync!
+      used_icons = scanner.scan_used_icons
+      stats = { copied: 0, removed: 0, kept: 0, errors: [] }
+
+      ICON_TYPES.each do |type|
+        sync_icons_for_type(type, used_icons[type] || [], stats)
+      end
+
+      log_sync_results(stats)
+      stats
+    end
+
+    # Dry run - shows what would be synced without making changes
+    def dry_run
+      used_icons = scanner.scan_used_icons
+      report = { would_copy: [], would_remove: [], would_keep: [] }
+
+      ICON_TYPES.each do |type|
+        analyze_sync_for_type(type, used_icons[type] || [], report)
+      end
+
+      report
+    end
+
+    private
+
+    def sync_icons_for_type(type, used_icon_names, stats)
+      app_icons_dir = app_icons_path(type)
+      gem_icons_dir = gem_icons_path(type)
+
+      # Create directory if it doesn't exist
+      FileUtils.mkdir_p(app_icons_dir) unless used_icon_names.empty?
+
+      # Get currently existing icons in app
+      existing_icons = existing_app_icons(type)
+
+      # Copy used icons that don't exist or are outdated
+      used_icon_names.each do |icon_name|
+        icon_file = "#{icon_name}.svg"
+        gem_icon_path = File.join(gem_icons_dir, icon_file)
+        app_icon_path = File.join(app_icons_dir, icon_file)
+
+        if File.exist?(gem_icon_path)
+          if !File.exist?(app_icon_path) || file_needs_update?(gem_icon_path, app_icon_path)
+            FileUtils.cp(gem_icon_path, app_icon_path)
+            stats[:copied] += 1
+          else
+            stats[:kept] += 1
+          end
+        else
+          stats[:errors] << "Icon not found in gem: #{type}/#{icon_name}"
+        end
+      end
+
+      # Remove icons that are no longer used
+      unused_icons = existing_icons - used_icon_names.map { |n| "#{n}.svg" }
+      unused_icons.each do |icon_file|
+        app_icon_path = File.join(app_icons_dir, icon_file)
+        FileUtils.rm(app_icon_path) if File.exist?(app_icon_path)
+        stats[:removed] += 1
+      end
+
+      # Remove directory if empty
+      FileUtils.rmdir(app_icons_dir) if Dir.empty?(app_icons_dir) && Dir.exist?(app_icons_dir)
+    rescue => e
+      stats[:errors] << "Error syncing #{type} icons: #{e.message}"
+    end
+
+    def analyze_sync_for_type(type, used_icon_names, report)
+      existing_icons = existing_app_icons(type)
+      gem_icons_dir = gem_icons_path(type)
+
+      used_icon_names.each do |icon_name|
+        icon_file = "#{icon_name}.svg"
+        app_icon_path = File.join(app_icons_path(type), icon_file)
+
+        if File.exist?(app_icon_path)
+          report[:would_keep] << "#{type}/#{icon_file}"
+        elsif File.exist?(File.join(gem_icons_dir, icon_file))
+          report[:would_copy] << "#{type}/#{icon_file}"
+        end
+      end
+
+      unused_icons = existing_icons - used_icon_names.map { |n| "#{n}.svg" }
+      unused_icons.each do |icon_file|
+        report[:would_remove] << "#{type}/#{icon_file}"
+      end
+    end
+
+    def app_icons_path(type)
+      File.join(rails_root, "app/assets/images/icons/#{type}")
+    end
+
+    def gem_icons_path(type)
+      File.join(Heroicons.root, "app/assets/images/icons/#{type}")
+    end
+
+    def existing_app_icons(type)
+      icons_dir = app_icons_path(type)
+      return [] unless Dir.exist?(icons_dir)
+
+      Dir.children(icons_dir).select { |f| f.end_with?(".svg") }
+    end
+
+    def file_needs_update?(source, destination)
+      File.mtime(source) > File.mtime(destination)
+    rescue
+      true
+    end
+
+    def log_sync_results(stats)
+      return unless Rails.logger
+
+      Rails.logger.info("[Heroicons] Icon sync complete:")
+      Rails.logger.info("  - Copied: #{stats[:copied]}")
+      Rails.logger.info("  - Removed: #{stats[:removed]}")
+      Rails.logger.info("  - Kept: #{stats[:kept]}")
+
+      stats[:errors].each do |error|
+        Rails.logger.warn("  - #{error}")
+      end
+    end
+  end
+end
diff --git a/lib/tasks/heroicons.rake b/lib/tasks/heroicons.rake
new file mode 100644
index 0000000..bd8c81d
--- /dev/null
+++ b/lib/tasks/heroicons.rake
@@ -0,0 +1,75 @@
+namespace :heroicons do
+  desc "Sync icons: copy used icons from gem to app/assets, remove unused ones"
+  task sync: :environment do
+    require "heroicons-rails"
+
+    puts "Scanning application for icon usage..."
+    syncer = Heroicons::IconSyncer.new
+
+    stats = syncer.sync!
+
+    puts "\n✓ Icon sync complete!"
+    puts "  #{stats[:copied]} icons copied"
+    puts "  #{stats[:removed]} icons removed"
+    puts "  #{stats[:kept]} icons already up to date"
+
+    if stats[:errors].any?
+      puts "\n⚠ Warnings:"
+      stats[:errors].each { |err| puts "  - #{err}" }
+    end
+  end
+
+  desc "Show which icons would be synced (dry run)"
+  task dry_run: :environment do
+    require "heroicons-rails"
+
+    puts "Analyzing icon usage..."
+    syncer = Heroicons::IconSyncer.new
+
+    report = syncer.dry_run
+
+    puts "\n--- Dry Run Report ---"
+
+    if report[:would_copy].any?
+      puts "\nWould COPY (#{report[:would_copy].size}):"
+      report[:would_copy].each { |icon| puts "  + #{icon}" }
+    end
+
+    if report[:would_remove].any?
+      puts "\nWould REMOVE (#{report[:would_remove].size}):"
+      report[:would_remove].each { |icon| puts "  - #{icon}" }
+    end
+
+    if report[:would_keep].any?
+      puts "\nWould KEEP (#{report[:would_keep].size}):"
+      report[:would_keep].each { |icon| puts "  = #{icon}" }
+    end
+
+    puts "\nRun 'rake heroicons:sync' to apply these changes."
+  end
+
+  desc "List all icons currently used in the application"
+  task list_used: :environment do
+    require "heroicons-rails"
+
+    puts "Scanning application for icon usage...\n"
+    scanner = Heroicons::IconScanner.new
+
+    used_icons = scanner.scan_used_icons
+
+    if used_icons.empty?
+      puts "No icons found in use."
+    else
+      total = used_icons.values.sum(&:size)
+      puts "Found #{total} unique icons in use:\n\n"
+
+      used_icons.each do |type, icons|
+        next if icons.empty?
+
+        puts "#{type.to_s.upcase} (#{icons.size}):"
+        icons.each { |icon| puts "  - #{icon}" }
+        puts ""
+      end
+    end
+  end
+end
diff --git a/test/heroicons_rails/icon_scanner_test.rb b/test/heroicons_rails/icon_scanner_test.rb
new file mode 100644
index 0000000..9495c35
--- /dev/null
+++ b/test/heroicons_rails/icon_scanner_test.rb
@@ -0,0 +1,73 @@
+require "test_helper"
+
+class Heroicons::IconScannerTest < ActiveSupport::TestCase
+  test "scans icon_tag calls with icon names" do
+    scanner = Heroicons::IconScanner.new(Rails.root)
+    content = <<~RUBY
+      <%= icon_tag :home %>
+      <%= icon_tag "user" %>
+      <%= icon_tag :x_mark, type: :solid %>
+    RUBY
+
+    used_icons = Hash.new { |h, k| h[k] = Set.new }
+    scanner.send(:extract_icons_from_content, content, used_icons)
+
+    assert_includes used_icons[:outline], "home"
+    assert_includes used_icons[:outline], "user"
+    assert_includes used_icons[:solid], "x-mark" # Should normalize underscores
+  end
+
+  test "normalizes underscored icon names to dashes" do
+    scanner = Heroicons::IconScanner.new(Rails.root)
+    content = "<%= icon_tag :academic_cap %>"
+
+    used_icons = Hash.new { |h, k| h[k] = Set.new }
+    scanner.send(:extract_icons_from_content, content, used_icons)
+
+    assert_includes used_icons[:outline], "academic-cap"
+    assert_not_includes used_icons[:outline], "academic_cap"
+  end
+
+  test "detects icon types correctly" do
+    scanner = Heroicons::IconScanner.new(Rails.root)
+    content = <<~RUBY
+      <%= icon_tag :home %>
+      <%= icon_tag :check, type: :solid %>
+      <%= icon_tag :star, type: :mini %>
+      <%= icon_tag :bell, type: :micro %>
+    RUBY
+
+    used_icons = Hash.new { |h, k| h[k] = Set.new }
+    scanner.send(:extract_icons_from_content, content, used_icons)
+
+    assert_includes used_icons[:outline], "home"
+    assert_includes used_icons[:solid], "check"
+    assert_includes used_icons[:mini], "star"
+    assert_includes used_icons[:micro], "bell"
+  end
+
+  test "handles various syntax formats" do
+    scanner = Heroicons::IconScanner.new(Rails.root)
+    content = <<~RUBY
+      <%= icon_tag(:home) %>
+      <%= icon_tag :user, class: "w-4 h-4" %>
+      <%= icon_tag "settings" %>
+      <%= icon_tag("menu") %>
+    RUBY
+
+    used_icons = Hash.new { |h, k| h[k] = Set.new }
+    scanner.send(:extract_icons_from_content, content, used_icons)
+
+    assert_includes used_icons[:outline], "home"
+    assert_includes used_icons[:outline], "user"
+    assert_includes used_icons[:outline], "settings"
+    assert_includes used_icons[:outline], "menu"
+  end
+
+  test "returns empty hash on scan error" do
+    scanner = Heroicons::IconScanner.new("/nonexistent/path")
+    result = scanner.scan_used_icons
+
+    assert_equal({}, result)
+  end
+end
diff --git a/test/heroicons_rails/icon_syncer_test.rb b/test/heroicons_rails/icon_syncer_test.rb
new file mode 100644
index 0000000..b84aae6
--- /dev/null
+++ b/test/heroicons_rails/icon_syncer_test.rb
@@ -0,0 +1,83 @@
+require "test_helper"
+require "fileutils"
+require "tmpdir"
+require "minitest/mock"
+
+class Heroicons::IconSyncerTest < ActiveSupport::TestCase
+  def setup
+    @temp_dir = Dir.mktmpdir
+    @mock_scanner = Minitest::Mock.new
+  end
+
+  def teardown
+    FileUtils.rm_rf(@temp_dir) if @temp_dir && Dir.exist?(@temp_dir)
+  end
+
+  test "dry_run returns report without making changes" do
+    @mock_scanner.expect(:scan_used_icons, { outline: ["home", "user"] })
+
+    syncer = Heroicons::IconSyncer.new(@temp_dir, scanner: @mock_scanner)
+    report = syncer.dry_run
+
+    assert_respond_to report, :[]
+    assert_includes report.keys, :would_copy
+    assert_includes report.keys, :would_remove
+    assert_includes report.keys, :would_keep
+
+    @mock_scanner.verify
+  end
+
+  test "sync! returns stats with counts" do
+    @mock_scanner.expect(:scan_used_icons, {})
+
+    syncer = Heroicons::IconSyncer.new(@temp_dir, scanner: @mock_scanner)
+    stats = syncer.sync!
+
+    assert_respond_to stats, :[]
+    assert_includes stats.keys, :copied
+    assert_includes stats.keys, :removed
+    assert_includes stats.keys, :kept
+    assert_includes stats.keys, :errors
+
+    @mock_scanner.verify
+  end
+
+  test "gem_icons_path returns correct path" do
+    syncer = Heroicons::IconSyncer.new(@temp_dir)
+    path = syncer.send(:gem_icons_path, :outline)
+
+    assert_includes path, "app/assets/images/icons/outline"
+    assert_includes path, Heroicons.root
+  end
+
+  test "app_icons_path returns correct path" do
+    syncer = Heroicons::IconSyncer.new(@temp_dir)
+    path = syncer.send(:app_icons_path, :solid)
+
+    assert_includes path, "app/assets/images/icons/solid"
+    assert_includes path, @temp_dir
+  end
+
+  test "existing_app_icons returns empty array for nonexistent directory" do
+    syncer = Heroicons::IconSyncer.new(@temp_dir)
+    icons = syncer.send(:existing_app_icons, :outline)
+
+    assert_equal [], icons
+  end
+
+  test "existing_app_icons returns svg files from directory" do
+    icons_dir = File.join(@temp_dir, "app/assets/images/icons/outline")
+    FileUtils.mkdir_p(icons_dir)
+    FileUtils.touch(File.join(icons_dir, "home.svg"))
+    FileUtils.touch(File.join(icons_dir, "user.svg"))
+    FileUtils.touch(File.join(icons_dir, "readme.txt")) # Should be ignored
+
+    syncer = Heroicons::IconSyncer.new(@temp_dir)
+    icons = syncer.send(:existing_app_icons, :outline)
+
+    assert_equal 2, icons.size
+    assert_includes icons, "home.svg"
+    assert_includes icons, "user.svg"
+    assert_not_includes icons, "readme.txt"
+  end
+end