Don't remove the name field. Also, the name of this DF should be Kani Kani No Mi, Moderu: Sen (Crab Crab Fruit, Model: Hermit)
Secondly, DF:s are somewhat averse to water, and most species of hermit crab are aquatic, making this somewhat questionable as a devil fruit, as you're essentially making an aquatic zoan.
Also, hermit crabs don't have shells. They pilfer abandoned gastropod shells. Even if this were not an aquatic crab zoan, it'd still need more description to be approvable.