"Bots," short for "robots," are a special category of users on Everything2 that are not normally operated by an actual human being and perform various automated tasks and functions on the site. In this writeup, I will briefly introduce various bots (including "retired" bots) that were created by the E2 administration and might be considered "official" bots.
I have not included any number of special users, sometimes also referred to as "bots" that were created by E2 members as part of autonoding projects or in order to store public domain works, in part because they are rarely encountered unless searching for specific topics and many do not actually serve any automated function and thus are not "true" bots. But mostly I have not included them because there are too many to exhaustively catalog and many of them have origins and purposes that are quite obscure.
So anyway, without further ado, here is a list of the most prominent E2 "bots" and a brief description of their functions
automaus
In the early days of E2, the database had to shut down once a day so that various chron jobs could be run. Automaus was a bot who would suddenly appear in the chatterbox to warn users that the database was about to shut down, and would gradually count down to the shutdown time. This was automaus's sole function, and once the database was set up to run continuously, he became obsolete and was "retired."
Cool Man Eddie
Cool Man Eddie is a bot who was originally created to automatically send a message to users when one of their writeups is awarded a C! Eddie continues to serve this function, but over the years his role has expanded to message users when they receive a variety of other goodies from another user, such as easter eggs, tokens, stars, extra C!s to spend, extra votes, sanctifications, etc. Cool Man Eddie is known for his perhaps mildly racist "jive talk" style of diction.
E2D2
E2D2 is a chatterbox bot designed and maintained by user in10se. Although in10se happens to be a member of the administration, E2D2 is not an "offical" bot but rather a private project. E2D2 has a wide variety of functions and responds to a number of different types of queries. E2D2 is notable for his extensive use of Markov chains to produce occasionally sensical spontaneous responses. More details can be found in the E2D2 node.
EDB
EDB, short for the "Everything Death Borg" is a bot used to "borg" people in the chatterbox who a member of the chanops team has seen fit to silence. When a user is borged, a humorous message from among several options appears in the chatterbox stating that EDB has eaten that user. The user is then prevented from speaking in the chatterbox for a certain number of minutes, using a complex formula that takes into account the number of times they have been borged in the past. In recent years EDB has been almost totally retired, although contrary to a popular myth, the code still exists and can be used by a member of chanops if necessary. But despite his retirement and his rough treatment of noders in the past, EDB has become a beloved member of the E2 community and occasionally appears in the chatterbox to pretend borg people and make cryptic pronouncements in extremely poor English grammar.
fireball
Fireball is a bot who sends users an automated private message whenever they are "fireballed" by another user in the chatterbox. Users fireballed in this way receive 5 GP. Judging from the bot's homenode picture, s/he (it?) is little more than a ball of flame.
Giant Teddy Bear
Giant Teddy Bear is a bot who occasionally appears in the chatterbox and "hugs" random users. Each time this happens the hugged users are awarded 2 GP. Giant Teddy Bear is usually silent, aside from his hugs.
Klaproth
In the early days of E2, if a Content Editor deleted your writeup, you would receive a message from Klaproth informing you of the removal and sometimes, informing you of the reason why. In an effort to increase editorial accountability, Klaproth was eventually retired, and today anytime a writeup is removed the author automatically receives a message from the removing editor themself and the editor is required to give a reason for the removal. Today, Klaproth is rumored to be enjoying his retirement in Mexico. Klaproth was named after the character in Neil Gaiman's Sandman comic series, although his homenode picture is a portrait of the real-life chemist, Martin Heinrich Klaproth.
root
Root is a somewhat rarely encountered bot who sends automated messages to users when their message to a usergroup was blocked by one or more users, and in a few other rare cases. Root never appears in the catbox.
Virgil
Virgil (yes, we know the name is "misspelled") is the E2 helpbot. Virgil sends automated messages in response to /help queries. Virgil also serves as a receptacle for E2 Help documents.
Webster 1913
Webster 1913 is E2's dictionary, chosen because his writings are in the public domain, and autonoded in order to obviate the need for users to node short definitions. Webby, as he is affectionately known, is E2's most prolific author and occasionally even writes non-definition writeups, notable for their incredibly extensive use of English vocabulary. If you /msg Webster 1913 with typos in his writeups, he may reply to you with a short note of thanks. Unknown to many users, these notes are also mini-blessings that award the recipient 3 GP.