asterisk/doc/tex/cliprompt.tex

\subsubsection{Changing the CLI Prompt}

The CLI prompt is set with the ASTERISK\_PROMPT UNIX environment variable that
you set from the Unix shell before starting Asterisk

You may include the following variables, that will be replaced by
the current value by Asterisk:

\begin{itemize}
    \item \%d - Date (year-month-date)
    \item \%s - Asterisk system name (from asterisk.conf)
    \item \%h - Full hostname
    \item \%H - Short hostname
    \item \%t - Time
    \item \%u - Username
    \item \%g - Groupname
    \item \%\% - Percent sign
    \item \%\# - '\#' if Asterisk is run in console mode, '$>$' if running as remote console
    \item \%Cn[;n] - Change terminal foreground (and optional background) color to specified
    A full list of colors may be found in \path{include/asterisk/term.h}
\end{itemize}

On systems which implement getloadavg(3), you may also use:

\begin{itemize}
    \item \%l1 - Load average over past minute
    \item \%l2 - Load average over past 5 minutes
    \item \%l3 - Load average over past 15 minutes
\end{itemize}