It would be nice if Gerrit trigger plugin included the message a comment-added event results in as an environmental variable. It looks like that "gerrit stream-events" includes comment texts as part of the data that it provides. But currently there doesn't seem to be a mechanism to get the exact comment that this event is triggered upon. Only the change reference is included and from it it's just a guess that which comments triggers this event, as those comments need to be separately fetched from Gerrit by using GERRIT_PATCHSET_REVISION environmental variable and there can be new comments added between the triggering and actually fetching the list of comments that a patch set has.