Because we grow and are weary of the countless issues horrible lua programmers modify chat text, we never have or will modify outbound chat.
We only monitor inbound text for "!", and even then, at such an non-invasive level, most other horribly written chat monitoring functions that look for "!" almost always over-ride ours 99.9% of the time.
TL;DR
No, we don't have chat tags, unless you consider our psay and asay commands, which technically are not chat tags, but print messages to those players with seeasay and or targeted in the command.