diff --git a/app/Form/Actions/ParticipantIndexAction.php b/app/Form/Actions/ParticipantIndexAction.php
index bb7e3a5f..8e260a7c 100644
--- a/app/Form/Actions/ParticipantIndexAction.php
+++ b/app/Form/Actions/ParticipantIndexAction.php
@@ -6,7 +6,6 @@ use App\Form\Models\Form;
 use App\Form\Models\Participant;
 use App\Form\Resources\ParticipantResource;
 use App\Form\Scopes\ParticipantFilterScope;
-use Illuminate\Database\Eloquent\Relations\HasMany;
 use Illuminate\Http\Resources\Json\AnonymousResourceCollection;
 use Laravel\Scout\Builder;
 use Lorisleiva\Actions\Concerns\AsAction;
@@ -16,7 +15,7 @@ class ParticipantIndexAction
     use AsAction;
 
     /**
-     * @return HasMany<Participant>
+     * @return Builder<Participant>
      */
     protected function getQuery(Form $form, ParticipantFilterScope $filter): Builder
     {
diff --git a/app/Form/Fields/Field.php b/app/Form/Fields/Field.php
index 043d1c07..c334dd07 100644
--- a/app/Form/Fields/Field.php
+++ b/app/Form/Fields/Field.php
@@ -180,4 +180,10 @@ abstract class Field extends Data
     {
         return app(SingleValueMatcher::class);
     }
+
+    /** @param mixed $value */
+    public function filter($value): string
+    {
+        return '';
+    }
 }
diff --git a/app/Form/Models/Participant.php b/app/Form/Models/Participant.php
index f28247e6..96c446ca 100644
--- a/app/Form/Models/Participant.php
+++ b/app/Form/Models/Participant.php
@@ -104,11 +104,12 @@ class Participant extends Model implements Preventable
         return 'Nachweise erforderlich für deine Anmeldung zu ' . $this->form->name;
     }
 
-    public function searchableAs()
+    public function searchableAs(): string
     {
         return $this->form->participantsSearchableAs();
     }
 
+    /** @return array<string, mixed> */
     public function toSearchableArray(): array
     {
         return [...$this->data, 'parent-id' => $this->parent_id];
diff --git a/app/Form/Scopes/ParticipantFilterScope.php b/app/Form/Scopes/ParticipantFilterScope.php
index 7f3606ed..e34baa41 100644
--- a/app/Form/Scopes/ParticipantFilterScope.php
+++ b/app/Form/Scopes/ParticipantFilterScope.php
@@ -13,7 +13,7 @@ use Spatie\LaravelData\Attributes\MapOutputName;
 use Spatie\LaravelData\Mappers\SnakeCaseMapper;
 
 /**
- * @extends Filter<Participant>
+ * @extends ScoutFilter<Participant>
  */
 #[MapInputName(SnakeCaseMapper::class)]
 #[MapOutputName(SnakeCaseMapper::class)]
@@ -25,6 +25,7 @@ class ParticipantFilterScope extends ScoutFilter
 
     /**
      * @param array<string, mixed> $data
+     * @param array<string, mixed> $options
      */
     public function __construct(
         public array $data = [],