Download using npm and browning

Question

I am trying to use only npm to create my project (therefore I do not want to use gulp or grunt).

I want to reload the page every time any project files change, but I cannot figure out how to do this. Can someone help me how will I need to use, for example, to download in this example ?:

 "scripts": {
    "build": "browserify js/index.js > build/index.js -vd",
    "start": "watchify js/index.js -o build/index.js -vd & serve . -p 3001 & opener http://localhost:3000"
  }

Thank! RBZA