Is it possible to do Dynamic Tagging

Hey Guys,

Quick question using RavenJS is it possible to do some kind of dynamic tagging based on things like “error text” or “source of error” or some xyz parameter.
What I am looking for is the possibility to add a small js function which can be part of the config or just plugged in later, which basically gets called on every eligible error (say after whitelistUrl is done) tags that error (or return tags) before sending it off to sentry servers.