Using this integration method, you call the HTTP endpoints directly to integrate with the core recommendations tracking API.
To set up the Optimizely Recommendations, provide Optimizely with a product catalog feed. See [Catalog feed specification](🔗).
The Server-to-Server API lets clients integrate their servers or applications with Optimizely Recommendations products. The API provides JSON tracking data and receives JSON-formatted content, calling the HTTP endpoints directly.
The core of the tracking data includes user journey, user information, and product details. In response to the tracking data sent, recommendations are returned with the Server-to-Server API response payload.
The following image shows an overview of the integration process.