You can use this endpoint to register your service. The args object can be used to further filter which candidate events you want to receive. The employee-related events do not use it, so it is advised not to include it.

For Recruiting events, if the args object is present, job_shortcode and stage_slug are required. If you want it for all jobs and stages, include an empty string as a parameter for each.
"job_shortcode": ""
"stage_slug": ""

The target URLs should be unique. If a target URL is already registered, the service will respond with 409 - Conflict.