# 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.

It is recommended that the processing time of the partner_side_catalog  webhook  is less than 3 seconds.

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