> For the complete documentation index, see [llms.txt](https://foodcommerce-api-help.onlinesales.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://foodcommerce-api-help.onlinesales.ai/user-tracking-events/api/register-ad-impressions.md). # Register Ad Impressions In order to track impressions for onsite sponsored ads, a marketplace needs to make following API call. This is needed in order to track the impressions and CTR's accurately. ### Endpoint GET `https://t.o-s.io/appsflyer` Following is the list of all possible query parameters to be passed to above endpoint: | Parameter | Description | Mandatory | | ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------- | --------- | | uclid | Ad server id. This id is returned as a part of the response of ad server call. | Yes | | event\_name | This value is fixed to `funnel_impression` | Yes | | event\_time | Time of the event. Defaults to the time of event fire. | No | | client\_id | Identifier for your account | Yes | | device\_id | The unique identifier for the user currently performing the action. Use GAID or IDFA in case of Android or iOS respectively. | No | | cli\_ubid | Client's generated user id. If sent, this takes precedence over `device_id` Once generated for a user - should be the same for all the api calls. | No | {% hint style="info" %} Please note : If the impressions are registered multiple times for the same `uclid`then, only the 1st event fire will be considered. {% endhint %} ### What should be considered as an Impression? When the sponsored product is visible to the user impression event should be fired. This is important in order to compute the correct CTR.