# 2026-05-11: Cart Service - batch update endpoint for cart items

## Overview

The Cart Service API reference now documents a new batch update endpoint for cart items. You can update multiple items in a cart in a single request using `PUT /cart/{tenant}/carts/{cartId}/itemsBatch`. The response for `POST /cart/{tenant}/carts/{cartId}/itemsBatch` was extended with the `index` property in each batch entry.

## New endpoints

| Endpoint                                                                                                                                                                   | Description                                                                                                                                |
| -------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------ |
| [Updating multiple products in cart](https://developer.emporix.io/api-references/api-guides/checkout/cart/api-reference/cart-items#put-cart-update-multiple-items-in-cart) | New endpoint for updating multiple cart items in one request. The number of cart items that can be edited in one request is limited to 50. |

## Updated endpoints

| Endpoint                                                                                                                                                               | Description                                                                                                               |
| ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------- |
| [Adding multiple products to cart](https://developer.emporix.io/api-references/api-guides/checkout/cart/api-reference/cart-items#post-cart-add-multiple-items-to-cart) | Response for `POST /cart/{tenant}/carts/{cartId}/itemsBatch` was extended with the `index` property for each batch entry. |

## Known problems

There are no known problems.


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