Mark - there are no indications at all, no dynamics, no pick control, and just the occasional LH finger number. They are not specifically for plectrum or fingers, or archtops or classical guitars. I found the experience very much like being faced with a Bach prelude, just single notes, and your job is to work out all the phrases, dynamics, tone changes, etc. This particular piece has a heavy baroque influence, but most of them don't. I've started another one, with dropped D tuning. Keys covered are mostly, but not always, "guitar keys". Some are moderate in speed, but quite a few are allegro or even presto.
Pat - as mentioned above, they are not really jazz pieces. William Bay is influenced by jazz and classical equally, and as you work through the book you will hear those influences coming and going. If nothing else, they are brilliant sight-reading exercises. But I find them very tuneful, and fun to play.