Since I\'ve found mush in the manual which is either not implemented or is not current, I speak from experience and observations. (Even with the recent recalculations.)
Hit points seem to definitely depend on strengthe and endurance, possibly also agility, will has an effect, but also experience (not as rolling stat, but overall).
Explanation:
The characters I\'ve played got more hit points with more combat experience.
Also, the more strength and endurance, the more hitpoints.
However, agility largely affect how often one gets hit--so may only seem to affect hit points.
High will characters are tenaciosly tough, low willed characters seem to give up their last 12% of hit points.
Very strong, and endurance characters last through many hits--also, very strong hit very hard--so strenth can win a fight before monster has chance to knock out the hp.
but so little time spent in each character that I don\'t know what it would be like if all stats were over 100--I do know that when one stat goes over 100, major improvement for all things related to that stat.
***I forgot to add that low endurance characters don\'t seem to lose much hp, but run out of steam to fight--so if fighting a highly aggressive npc, you run or you dead.