Which API enables Tableau to send notifications when a data source refreshes?

The Webhooks API is the correct choice because it is specifically designed to handle notifications based on certain events occurring within Tableau, such as the refresh of a data source. When a data source is refreshed, the Webhooks API can trigger notifications to registered endpoints, effectively informing them of the update. This capability allows users to integrate Tableau with other applications or workflows, ensuring that relevant stakeholders are alerted immediately when data changes occur.

In contrast, the REST API primarily focuses on resource management, allowing users to interact with Tableau Server or Tableau Online for tasks such as creating users, managing projects, or publishing workbooks. The Document API is used for programmatic access to Tableau documents to automate processes like modifying or creating Tableau workbooks. The Metadata API provides access to metadata about the Tableau environment, which is useful for understanding data lineage and governance but does not handle notifications related to data refresh events.