Adding labels - Standard error bar chart
Below is a worked example of adding labels to a standard error bar chart:

The commands I used in a do-file are:
webuse assembly, clear
generate upper=mean+2*std
serrbar mean std date, scale(2) yline(195) ///
addplot( scatter up date, msymbol(none) mlabel(upper))
For more information on Stata graphs, please have a look at the book A Visual Guide to Stata Graphics