What type of response indicates a successful health check?

A successful health check is indicated by an HTTP status code 200. This status code means "OK," signaling that the service is up, running, and capable of properly processing requests. In the context of health checks, services often respond with this code when they are healthy and ready to accept traffic, allowing monitoring systems to assess the status of an application correctly.

When a health check returns a status code like 404, it indicates that the requested resource could not be found, suggesting that there might be issues with service availability. An empty response would imply no connection or failure in reaching the service, which doesn't ascertain the health status effectively. A status code of 500 indicates a server error and signifies that something went wrong on the server's side, reflecting an unhealthy state. Hence, among the provided choices, an HTTP status code of 200 clearly denotes a successful health check, demonstrating that the service is operational.