Team:
As of today incoming request data includes an extra bit of information on the X-analytics header.
If an incoming request to any wikipedia project had no cookies whatsoever it will be tagged with nocookie=1. A requests without any cookies could correspond to a fresh browser session, a user browsing with cookies disabled or, most likely, a bot request as most bots will not accept cookies. We *might* be able to use this setting as a cheap proxy to quantify bot traffic.
Documentation about this change can be found here: https://wikitech.wikimedia.org/wiki/X-Analytics
Thanks,
Nuria