Add more labels to each end of 3D axis

Question

I want to add some more labels at the end of each axis. For example, on the z axis I want to add 'up' (where z arrow points) and 'down' (opposite direction) as labels, 'right' and 'left' on x axis and so on. I used this code

\begin{tikzpicture}[x=0.5cm,y=0.5cm,z=0.3cm,>=stealth]
% The axes
\draw[->] (xyz cs:x=-13.5) -- (xyz cs:x=13.5) node[below] {$x$};
\draw[->] (xyz cs:y=-13.5) -- (xyz cs:y=13.5) node[right] {$z$};
\draw[->] (xyz cs:z=-13.5) -- (xyz cs:z=13.5) node[above] {$y$}; 
\end{tikzpicture} 

Answer 1

To expand my comment a bit, you can do exactly the same thing that you've done already for the $x$, $y$ and $z$, add a node[<position>] {<text>} after the coordinate where you want a label. One can insert multiple nodes at the same point in the path.

So more generally, you can do things like

\draw (0,0) node[left] {A1} node[above] {A2} node[below] {A3}
   -- (1,1) node[right] {B} node[below] {C};

Complete example with new labels for just the z-axis:

\documentclass[border=5mm]{standalone}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}[x=0.5cm,y=0.5cm,z=0.3cm,>=stealth]
% The axes
\draw[->] (xyz cs:x=-13.5) -- (xyz cs:x=13.5) node[below] {$x$};
\draw[->] (xyz cs:y=-13.5) node[below] {down} -- (xyz cs:y=13.5) node[right] {$z$} node[above] {up};
\draw[->] (xyz cs:z=-13.5) -- (xyz cs:z=13.5) node[above] {$y$}; 
\end{tikzpicture} 
\end{document}