The purpose of the Kibana URL helper tool is to provide a simple tool to inject filters and query parameters into an Kibana URL. That’s useful if you like to switch between different apps in Kibana and transfer some context at the same time. This can also be useful if you access Kibana via an IFrame and would like to define how the initial state of Kibana should look like.
The Kibana URL can influence the global state and the app state (afaik). In older version of Kibana the user was able to see the change of the state directly reflected in the URL. That was helpful to see how the URL needs to look like if you would like to influence the filters based on an external action. This was often used to e.g. navigate between dashboards by taking over a filter value.
Today Kibana supports Drill drowns and pinned filters across many of the Kibana apps. Because of that a custom drill down is not needed that often. But at the same time when Drill downs where introduced Kibana also changed its behaviour making the current state transparent in the URL. Leading to the fact that now you can’t see the state anymore directly after e.g. adding a query to the query bar. The good news is, that you still be able to influence the state in the same way it was in the past.
This Kibana URL parameter helper tool is for everyone who wants to influence the URL in the right way.