> For the complete documentation index, see [llms.txt](https://fredhopper.gitbook.io/product-discovery/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://fredhopper.gitbook.io/product-discovery/tracking-and-sending-events/implementation-guide/rest-api.md).

# REST API

Use the REST API to send custom activities: generate session IDs, create valid JSON activity objects, and make POST requests with your tracker key for tracking

To construct activities yourself and devise your own method of sending them, use the Rest API:

1. Generate your own **session ID** when sending activities via the Rest API.\
   More information on session IDs can be found in the [**Identities** section](/product-discovery/tracking-and-sending-events/identities.md).
2. Ensure that the request is a valid **activity object** in JSON format. The activity object must include the [user object](/product-discovery/tracking-and-sending-events/identities/user-object.md), i.e you have to generate a unique session ID for each user.\
   More information on the activity object can be found in the [**Activities** section](/product-discovery/tracking-and-sending-events/activities.md).
3. Make a **POST** request to the following URL with your [**tracker key**](/product-discovery/tracking-and-sending-events/setup-guide/prerequisites.md#optain-your-tracker-key-s):

<mark style="color:green;">`POST`</mark> `https://collect-eu.attraqt.io/:trackerKey`

{% hint style="info" %}
To obtain your tracker key(s), reach out to your Customer Support Manager.
{% endhint %}