Cat bite out of nowhere

So, I was sat at my desk with my cat sat peacefully beside me. I wasn't attending to her - she seemed to be peaceful (no tail flicks, no noise, no paw taps for attention). Unexpectedly she bit me quite hard on the wrist and, after a moment, ran off. She did not break skin, nor did she make any vocalisation, and she did not return to the room. Was this some sort of attempt to initiate play?

Context - I am her fifth home. She was surrendered for bullying other cats in her first home, then had couple of failed adoption attempts from the shelter, then my friend got her just before the pandemic and was planning to return her but got attached during lockdown. However, when she had a baby the cat's behaviour was so scary (yowling, a bizarre sort of slinking predatory advance on the infant that scared the hell out of me when I saw it) that she had to be re-homed 'temporarily' with me three years ago. She is now mine forever.

She is normally fine with me - I can pick her up, check inside her mouth and ears, even touch her paws most of the time, and she generally likes to sleep near or on me. She likes to play, and is quite good with tricks - she can do a twirl and jump up with two paws on the back of a chair for a treat. She does however have a Thing about the desk - I work a lot and I think she sees time spent typing as time wasted (point).

She is generally unpleasant to cat sitters and has bitten/swatted most of my visitors, but those were clearly attempts to get them to go away. This I am not sure of... if she really wanted to bite, surely she would have drawn blood?