diff --git a/app/code/Magento/QuoteGraphQl/Model/Cart/UpdateCartItems.php b/app/code/Magento/QuoteGraphQl/Model/Cart/UpdateCartItems.php
deleted file mode 100644
index c2148dbe09933..0000000000000
--- a/app/code/Magento/QuoteGraphQl/Model/Cart/UpdateCartItems.php
+++ /dev/null
@@ -1,58 +0,0 @@
-<?php
-declare(strict_types=1);
-/**
- * Copyright © Magento, Inc. All rights reserved.
- * See COPYING.txt for license details.
- */
-namespace Magento\QuoteGraphQl\Model\Cart;
-
-use Magento\Framework\Exception\NoSuchEntityException;
-use Magento\Quote\Model\Quote;
-use Magento\Quote\Api\CartRepositoryInterface;
-use Magento\Quote\Api\GuestCartRepositoryInterface;
-
-class UpdateCartItems
-{
-    /**
-     * @var CartRepositoryInterface
-     */
-    private $quoteRepository;
-
-    /**
-     * @var GuestCartRepositoryInterface
-     */
-    private $guestCartRepository;
-
-    public function __construct(
-        CartRepositoryInterface $quoteRepository,
-        GuestCartRepositoryInterface $guestCartRepository
-    ) {
-        $this->quoteRepository = $quoteRepository;
-        $this->guestCartRepository = $guestCartRepository;
-    }
-
-    public function update(string $maskedCartId, array $items): Quote
-    {
-        $quote = $this->guestCartRepository->get($maskedCartId);
-
-        foreach ($items as $item) {
-            $quoteItem = $quote->getItemById($item['item_id']);
-            if ($quoteItem === false) {
-                throw new NoSuchEntityException(__('Could not find cart item with id: %1', $item['item_id']));
-            }
-
-            $qty = $item['qty'];
-
-            if ($qty <= 0.0) {
-                $quote->removeItem($quoteItem->getItemId());
-                continue;
-            }
-
-            $quoteItem->setQty($qty);
-        }
-
-        $this->quoteRepository->save($quote);
-
-        return $quote;
-    }
-}
diff --git a/app/code/Magento/QuoteGraphQl/Model/Resolver/ApplyCouponToCart.php b/app/code/Magento/QuoteGraphQl/Model/Resolver/ApplyCouponToCart.php
index a334e7482ca47..ba38158b7fa7c 100644
--- a/app/code/Magento/QuoteGraphQl/Model/Resolver/ApplyCouponToCart.php
+++ b/app/code/Magento/QuoteGraphQl/Model/Resolver/ApplyCouponToCart.php
@@ -50,12 +50,12 @@ public function __construct(
      */
     public function resolve(Field $field, $context, ResolveInfo $info, array $value = null, array $args = null)
     {
-        if (!isset($args['input']['cart_id'])) {
+        if (!isset($args['input']['cart_id']) || empty($args['input']['cart_id'])) {
             throw new GraphQlInputException(__('Required parameter "cart_id" is missing'));
         }
         $maskedCartId = $args['input']['cart_id'];
 
-        if (!isset($args['input']['coupon_code'])) {
+        if (!isset($args['input']['coupon_code']) || empty($args['input']['coupon_code'])) {
             throw new GraphQlInputException(__('Required parameter "coupon_code" is missing'));
         }
         $couponCode = $args['input']['coupon_code'];
diff --git a/app/code/Magento/QuoteGraphQl/Model/Resolver/Cart.php b/app/code/Magento/QuoteGraphQl/Model/Resolver/Cart.php
index 2df31841366a1..db74b1fa4174b 100644
--- a/app/code/Magento/QuoteGraphQl/Model/Resolver/Cart.php
+++ b/app/code/Magento/QuoteGraphQl/Model/Resolver/Cart.php
@@ -37,7 +37,7 @@ public function __construct(
      */
     public function resolve(Field $field, $context, ResolveInfo $info, array $value = null, array $args = null)
     {
-        if (!isset($args['cart_id'])) {
+        if (!isset($args['cart_id']) || empty($args['cart_id'])) {
             throw new GraphQlInputException(__('Required parameter "cart_id" is missing'));
         }
         $maskedCartId = $args['cart_id'];
diff --git a/app/code/Magento/QuoteGraphQl/Model/Resolver/RemoveCouponFromCart.php b/app/code/Magento/QuoteGraphQl/Model/Resolver/RemoveCouponFromCart.php
index 730c927c32a0c..d0b4bfd9c7d3a 100644
--- a/app/code/Magento/QuoteGraphQl/Model/Resolver/RemoveCouponFromCart.php
+++ b/app/code/Magento/QuoteGraphQl/Model/Resolver/RemoveCouponFromCart.php
@@ -50,7 +50,7 @@ public function __construct(
      */
     public function resolve(Field $field, $context, ResolveInfo $info, array $value = null, array $args = null)
     {
-        if (!isset($args['input']['cart_id'])) {
+        if (!isset($args['input']['cart_id']) || empty($args['input']['cart_id'])) {
             throw new GraphQlInputException(__('Required parameter "cart_id" is missing'));
         }
         $maskedCartId = $args['input']['cart_id'];
diff --git a/app/code/Magento/QuoteGraphQl/Model/Resolver/RemoveItemFromCart.php b/app/code/Magento/QuoteGraphQl/Model/Resolver/RemoveItemFromCart.php
index 1838f17369ffc..2ff7af354368b 100644
--- a/app/code/Magento/QuoteGraphQl/Model/Resolver/RemoveItemFromCart.php
+++ b/app/code/Magento/QuoteGraphQl/Model/Resolver/RemoveItemFromCart.php
@@ -23,25 +23,25 @@
 class RemoveItemFromCart implements ResolverInterface
 {
     /**
-     * @var GuestCartItemRepositoryInterface
+     * @var GetCartForUser
      */
-    private $guestCartItemRepository;
+    private $getCartForUser;
 
     /**
-     * @var GetCartForUser
+     * @var GuestCartItemRepositoryInterface
      */
-    private $getCartForUser;
+    private $guestCartItemRepository;
 
     /**
-     * @param GuestCartItemRepositoryInterface $guestCartItemRepository
      * @param GetCartForUser $getCartForUser
+     * @param GuestCartItemRepositoryInterface $guestCartItemRepository
      */
     public function __construct(
-        GuestCartItemRepositoryInterface $guestCartItemRepository,
-        GetCartForUser $getCartForUser
+        GetCartForUser $getCartForUser,
+        GuestCartItemRepositoryInterface $guestCartItemRepository
     ) {
-        $this->guestCartItemRepository = $guestCartItemRepository;
         $this->getCartForUser = $getCartForUser;
+        $this->guestCartItemRepository = $guestCartItemRepository;
     }
 
     /**
@@ -49,12 +49,12 @@ public function __construct(
      */
     public function resolve(Field $field, $context, ResolveInfo $info, array $value = null, array $args = null)
     {
-        if (!isset($args['input']['cart_id'])) {
+        if (!isset($args['input']['cart_id']) || empty($args['input']['cart_id'])) {
             throw new GraphQlInputException(__('Required parameter "cart_id" is missing'));
         }
         $maskedCartId = $args['input']['cart_id'];
 
-        if (!isset($args['input']['cart_item_id'])) {
+        if (!isset($args['input']['cart_item_id']) || empty($args['input']['cart_item_id'])) {
             throw new GraphQlInputException(__('Required parameter "cart_item_id" is missing'));
         }
         $itemId = $args['input']['cart_item_id'];
diff --git a/app/code/Magento/QuoteGraphQl/etc/schema.graphqls b/app/code/Magento/QuoteGraphQl/etc/schema.graphqls
index 7e99dc636e974..f5b15212a2209 100644
--- a/app/code/Magento/QuoteGraphQl/etc/schema.graphqls
+++ b/app/code/Magento/QuoteGraphQl/etc/schema.graphqls
@@ -11,6 +11,7 @@ type Mutation {
     addVirtualProductsToCart(input: AddVirtualProductsToCartInput): AddVirtualProductsToCartOutput @resolver(class: "Magento\\QuoteGraphQl\\Model\\Resolver\\AddSimpleProductsToCart")
     applyCouponToCart(input: ApplyCouponToCartInput): ApplyCouponToCartOutput @resolver(class: "\\Magento\\QuoteGraphQl\\Model\\Resolver\\ApplyCouponToCart")
     removeCouponFromCart(input: RemoveCouponFromCartInput): RemoveCouponFromCartOutput @resolver(class: "\\Magento\\QuoteGraphQl\\Model\\Resolver\\RemoveCouponFromCart")
+    updateCartItems(input: UpdateCartItemsInput): UpdateCartItemsOutput @resolver(class: "Magento\\QuoteGraphQl\\Model\\Resolver\\UpdateCartItems")
     removeItemFromCart(input: RemoveItemFromCartInput): RemoveItemFromCartOutput @resolver(class: "Magento\\QuoteGraphQl\\Model\\Resolver\\RemoveItemFromCart")
     setShippingAddressesOnCart(input: SetShippingAddressesOnCartInput): SetShippingAddressesOnCartOutput @resolver(class: "\\Magento\\QuoteGraphQl\\Model\\Resolver\\SetShippingAddressesOnCart")
     setBillingAddressOnCart(input: SetBillingAddressOnCartInput): SetBillingAddressOnCartOutput @resolver(class: "\\Magento\\QuoteGraphQl\\Model\\Resolver\\SetBillingAddressOnCart")