Node / npm: How to manage globally installed devDependencies

I'm building a Node module with devDependencies that should be globally installed, such as jasmine-node and jshint. What I essentially need is to be able to reference their binaries in my makefile / npm scripts section to run tests, lint, etc. In other words I do not wish to require() them programmatically.

After digging around I'm still confused on how to handle this:

1) My first approach was to assume that these modules would be globally installed, clarify this in my module's documentation and reference their binaries as globals - i.e. expect them to be globally available. This conflicts with this piece of advice

Make sure you avoid referencing globally installed binaries. Instead, point it to the local node_modules, which installs the binaries in a hidden .bin directory. Make sure the module (in this case "mocha") is in your package.json under devDependencies, so that the binary is placed there when you run npm install.

(taken from this post)

This generally sounds right, as the aforementioned setup is rather fragile.

2) My next approach was explicitly including those modules in devDependencies (although they are still globally installed on my system (and most probably on users' & contributors' systems as well)). This ensures that appropriate versions of the binaries are there when needed and I can now reference them through node_modules/.bin/.

However I'm now in conflict with this piece of advice

Install it locally if you're going to require() it.

(taken from npm docs)

Regardless of that, I do notice that npm install will now actually fetch nothing (display no network activity) for the globally installed modules.

My questions:

• Are the local versions of globally installed modules (that are mentioned in devDependencies) just snapshots (copies) of the global ones, taken during npm install?
• Is 2) the correct way to go about doing this? or is there some other practice I'm missing?