Start with my page about mulches, and the pros and cons of different kids. If the chips are composted well BEFORE you use them and of a small enough texture, in my opinion, they are far more appropriate for use as mulch that is fresh out of a bag from the garden center and large-sized.
Details on how to evaluate a potential material as a mulch:
Welcome! I’m Margaret Roach, a leading garden writer for 25 years—at ‘Martha Stewart Living,’ ‘Newsday,’ and in three books. I host a public-radio podcast; I also lecture, plus hold tours at my 2.3-acre Hudson Valley (NY) Zone 5B garden, and always say no to chemicals and yes to great plants.