npm cache

bash-3.2$ npm clear cache

Usage: npm <command>

where <command> is one of:
    access, adduser, bin, bugs, c, cache, completion, config,
    ddp, dedupe, deprecate, dist-tag, docs, edit, explore, faq,
    get, help, help-search, i, init, install, install-test, it,
    link, list, ln, logout, ls, outdated, owner, pack, ping,
    prefix, prune, publish, rb, rebuild, repo, restart, root,
    run-script, s, se, search, set, shrinkwrap, star, stars,
    start, stop, t, tag, team, test, tst, un, uninstall,
    unpublish, unstar, up, update, v, version, view, whoami

npm <cmd> -h     quick help on <cmd>
npm -l           display full usage info
npm faq          commonly asked questions
npm help <term>  search for help on <term>
npm help npm     involved overview

Specify configs in the ini-formatted file:
    /Users/mona/.npmrc
or on the command line via: npm <command> --key value
Config info can be viewed via: npm help config