Jira Server base url information in webhooks/api

I need to redirect to a Jira issue based on webhook notification. As of now, all links in webhook payload are pointing to api endpoint(s). Generic domain.com/browse/issuekey works in most cases, but custom installations like domain.com/jira/ obviously doesn’t. Is there any way to get Jira base url from the webhook/api? Are there any options other than reroute custom route to / to deal with this issue?