Apart from the fact that bots usually behave in strange ways (see Bots or Humans? ), you can say it watching the score table: bots have ping 0, and usually (but not in all servers) a gun barrel in the first table column (named “Skill”). The number of bullets in the barrel (from 1 to 6) shows how much skilled the bot is.
Posted in: Smokin' Guns — Basics