# Catalog personalization on partner side

Xsolla will send a partner_side_catalog webhook that contains the user and project parameters to the webhook URL when a user interacts with the store.

Return a list of item_id or item SKU that are available to the user in response. In this case, you can also include information that a particular user can buy a certain product a specified number of times. This feature allows you to control the number and type of products that the user can add to the cart and buy.


  Notice
  When processing the webhook, consider the following limitations:The webhook must be processed in under 3 seconds. If processing takes longer, the get virtual items list, create payment token, and create order API calls return an error.The webhook response size mustn’t exceed 64 KB. Responses exceeding this limit are not processed — the user sees an empty catalog and can’t purchase any items. To change the maximum response size, contact your Customer Success Manager or email to csm@xsolla.com.

Endpoint: POST personalized-partner-catalog
Version: 1.0

## Request fields (application/json):

  - `user` (object, required)
    User details (object).

  - `user.user_id` (string, required)
    User ID. If the user is not authenticated, the value null is sent.

  - `user.country` (string)
    User’s country. Two-letter uppercase [ISO 3166-1 alpha-2](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2) country code.

  - `user.currency` (string)
    Currency. Three-letter currency code per [ISO 4217](https://en.wikipedia.org/wiki/ISO_4217).

  - `user.locale` (string)
    User language. Two-letter lowercase [language code](https://developers.xsolla.com/doc/pay-station/features/localization/).


## Response 404 fields