Run downloaded nodejs package

I've installed a nodejs package (module?) using

sudo npm install -g ng-annotate

How can I start it?

I've tried

npm run ng-annotate test

and it indeed runs some tests and they all pass. Nice, but replacing test by anything else produces no output at all and the return code is zero. For example,

npm run ng-annotate npn is a crap!

does nothing at all. I've also tried nodejs whatever, etc. What I want should look like

npm run ng-annotate run --add - < infile.js > outfile.js

I must confess I haven't read all the help available, but it's the very first tools which ignores all invalid inputs and keeps secret how to run it. I don't want to learn nodejs now; all I need is to run the script.