In the backdrop of interventional gastrointestinal endoscopy emerging as a sub-speciality, this narrative review examined the competency-based nursing responsibilities across the continuum of endoscopic care. Electronic databases including PubMed, Scopus, ScienceDirect, Google Scholar, and CINAHL were searched using keywords related to interventional endoscopy, endoscopy nursing, ERCP, EUS, sedation monitoring, infection prevention, competency-based training, and Objective Structured Clinical Examination (OSCE). Relevant literature was synthesised into major domains of endoscopy nursing practice. Technological innovations such as Endoscopic Retrograde Cholangiopancreatography, Endoscopic Ultrasound, Endoscopic Mucosal Resection, Endoscopic Submucosal Dissection (ESD), Per-Oral Endoscopic Myotomy, and capsule endoscopy have expanded therapeutic capabilities in gastrointestinal care. Nursing responsibilities now include comprehensive patient assessment, sedation monitoring, procedural assistance, infection prevention, complication recognition, discharge education, and quality assurance activities. OSCE-based assessment models support procedural safety and professional accountability. Advanced interventional endoscopy requires specialised nursing competencies to support patient safety, infection prevention, technical coordination, and high-quality patient-centred care.