UpdateContext

Default context looks like this:

public class BaseUpdateContext : IUpdateContext
{
    public Update Update { get; set; }
    public HttpContext HttpContext { get; set; }
    public TaskCompletionSource Result { get; set; }
    public IServiceProvider Services { get; set; }
    public UserState UserState { get; set; } = new UserState();
    public BaseBot Bot { get; set; }
    public TelegramBotClient Client { get; set; }
}

Update - current update object HttpContext and Result - objects for webhook scenarios handling Services - in case you need access to DI. Bot - your bot class instance with bot username and other settings Client - instance of telegram BOT api wrapper UserState instance of:

public class UserState
{
   public string Stage { get; set; } = "default";
   public int Step { get; set; }
   public Role Role { get; set; }
   public string LanguageCode { get; set; }
} 

All this fields used for Stages/States and describe each user individually.