Pretty much similar to the bone claws Wolverine had.
Harvard biologist David Blackburn also believes that once the claws are retracted, it’s possible for the frog’s damaged tissues to regenerate and heal almost instantly.
“Being amphibians, it would not be surprising if some parts of the wound heal and the tissue is regenerated�
What’s even weird about Trichobatrachus robustus is that the frog is also capable growing hair on its body during the mating season (check out the featured photo). Because, you know, females love men with hair đŸ˜‰
New Scientist