add php docstrings for methods

app/Http/Controllers/ItemController.php

@@ -3,6 +3,7 @@
 namespace App\Http\Controllers;
 
 use App\Data\ItemsCollection;
+use Illuminate\Http\JsonResponse;
 use Illuminate\Http\Request;
 
 class ItemController extends Controller
@@ -17,14 +18,22 @@ class ItemController extends Controller
         $this->itemsCollection = $itemsCollection;
     }
 
-    public function search(Request $request)
+    /**
+     * @param Request $request
+     * @return JsonResponse
+     */
+    public function search(Request $request): JsonResponse
     {
         return response()->json([
             'item' => $this->itemsCollection->findItem($request->input('query')),
         ]);
     }
 
-    public function getItem(string $id)
+    /**
+     * @param string $id
+     * @return JsonResponse
+     */
+    public function getItem(string $id): JsonResponse
     {
         return response()->json([
             'item' => $this->itemsCollection->getItemById($id),