Due to its delicate subject matter and challenging operations, neurosurgery has always been in need of adapting new techniques and technologies. A neurosurgical procedure that could especially benefit from the use of such technologies is the Endoscopic Endonasal Transsphenoidal Surgery (EETS), a minimally invasive neurosurgical technique that is performed via an anterior sphenoidotomy and aims at the removal of sellar and parasellar lesions with the use of an endoscope and rigid instruments. Current standard instruments lack articulation limiting operative access and surgeon dexterity, and thus, could benefit from robotic articulation. In this study, a handheld robotic system with a series of detachable end-effectors for this approach is presented. This system is comprised of an articulated 3 degrees-of-freedom 3mm grasper with a modular design that allows for instrument expansion, its ergonomically designed handheld controller with a rotating joystick-body that can be placed at the position most comfortable for the user, and the accompanying control box. The robotic instruments were experimentally evaluated for their workspace, structural integrity, and force-delivery capabilities during a cadaver pilot study by a cohort of neurosurgeons with varied clinical experience. Results from this pre-clinical experimental procedure showcased enhanced dexterity and adequate robustness that could suggest feasibility in a clinical context, as well as improvement over current neurosurgical instruments.