I've used Twilio for casual one-day projects and I don't think their documentation is a good example. They have a lot of resources and examples but it's very disjoint and hard to use. A better example would be Stripe.
For example, let's saying I'm trying to redirect an inbound call, a fairly trivial use case. Their nodejs doc doesn't have a section on inbound calls [0] at all. It's different from using your average RESTful API and you'd expect a trivial use case to be given as an example, as opposed to a section on callbacks vs promises.
Trying to find out the 'from' number from your /voice POST request? Good luck parsing out the req manually to figure out what you need because the doc doesn't tell you anything.
And there are things Twilio's neglected to do for no reason whatsoever. For instance, the methods for a TwimlResponse object is not documented on the node doc because the verbs are from TwiML. I get that <say> = TwiMLObject.say() but documenting this is trivial and makes it easier on the developer using the platform.
Anyway, that's my rant. Check out Stripe instead, OP.
[0] https://twilio.github.io/twilio-node/