Agent can host an HTTP(S) status endpoint which can be queried. This endpoint is enabled on the Agents when the HttpStatusinfoPort is set or when HTTP/HTTPS are configured for the Agent.
This endpoint is hosted at
/frendsstatusinfo on the HTTP for the HTTP ports and the HttpStatusinfoPort and on HTTPS for HTTPS ports. This endpoint just returns HTTP result code 200 (OK) if the Agent is running and not paused. It is used e.g. by API gateways for monitoring if the upstream execution Agents are running. It can of course also be used by external load-balancers configured for the systems.
If the Agent is paused, the endpoint will return 503 (Service unavailable). If you have API gateways set up, this is used to turn off traffic to Agents behind that gateway in a controlled way. The gateway will stop routing traffic to the paused Agent while it is paused.
The Cross-platform Agents additionally provide the amount of Processes currently executing on the Agent and has optional API-key authorization configurable with the HealthCheckApiKey -setting. The API key needs to be provided in a HTTP header named health-check-api-key.