... call it in your own code (should you feel the urge).
You:
put a peak list in the clipboard from your favourite mass spec viewing software,
append another list if you want (then you can merge lists together),
copy-out or save the MSP that appears in the right hand box.
Command line arguments:
/? displays help information - Start from here. There are a few of them.
And if this doesn't mean anything to you then this probably isn't the app for you
Happy MSPing