This plugin registers a ChecksProvider with the Gerrit UI that will fetch build results for a change from configured Jenkins servers and provide them to the checks panel in a change screen.
The Jenkins servers have to support CORS-requests. This can for example be achieved by using a reverse proxy that sets the Access-Control-Allow-Origin and Access-Control-Allow-Credentials header.
The Jenkins server additionally needs to install the gerrit-checks-api-plugin plugin that enables querying for job runs working on a given patchset.