Poison Needle Trap

Mechanical trap
A poisoned needle is hidden within a treasure chest's lock, or in something else that a creature might open. Opening the chest without the proper key causes the needle to spring out, delivering a dose of poison.
When the trap is triggered, the needle extends 3 inches straight out from the lock. A creature within range takes 1 Piercing Damage and 11 (2d10) Poison Damage, and must succeed on a DC 15 Constitution Saving Throw or be Poisoned for 1 hour.
A successful DC 20 Intelligence (Investigation) Skill Check allows a character to deduce the trap's presence from alterations made to the lock to accommodate the needle. A successful DC 15 Dexterity Ability Check using Thieves' tools disarms the trap, removing the needle from the lock. Unsuccessfully attempting to pick the lock triggers the trap.