My hermit crab is out of his shell-can you help me?

his eyes would not be black if he was molting ... i think you have a dying or dead crab ... the number one reason for them to leave their shells is something off in the environment ... if you want more hermit , you should do more research on how they should be kept because they should live over 15 years if kept correctly ... and you never keep one hermit crab ... in the wild (all hermit are taken from the wild) they travel in huge colonies so one alone is not a good idea ... one hermit crab kept alone is stressed, stress leads to illness and illness to death ... i would not toss him out yet but from your description it does not sound good ... if he was to molt he would bury in the substrate and you would not see him for a week or more depending on the size of the crab ... and when they molt and look like they are hanging out of the shell, that is the exoskeleton shed hanging out and the eyes are not black at that point ...