diff --git a/src/MakeBom/Options.php b/src/MakeBom/Options.php
index 33103f82..1b86e91d 100644
--- a/src/MakeBom/Options.php
+++ b/src/MakeBom/Options.php
@@ -31,6 +31,8 @@
 use Symfony\Component\Console\Input\InputOption;
 
 /**
+ * @psalm-type TOmittable='dev'|'plugin'
+ *
  * @internal
  *
  * @author jkowalleck
@@ -50,6 +52,7 @@ class Options
     /**
      * Possible output formats.
      * First in list is the default value.
+     * @psalm-var non-empty-list<Format::*>
      */
     private const VALUES_OUTPUT_FORMAT = [
         Format::XML,
@@ -58,6 +61,10 @@ class Options
 
     public const VALUE_OUTPUT_FILE_STDOUT = '-';
 
+    /**
+     * Possible omittables.
+     * @psalm-var non-empty-list<TOmittable>
+     */
     private const VALUES_OMIT = [
         'dev',
         'plugin',
@@ -164,7 +171,7 @@ public function configureCommand(Command $command): Command
      *
      * @var string[]
      *
-     * @psalm-var list<'dev'|'plugin'>
+     * @psalm-var list<TOmittable>
      *
      * @psalm-allow-private-mutation
      */