OpenAPI 3.1 specification for the ROBUST-6G Work Package 6 physical-layer security demonstrator. The component exposes three capabilities over a stateless REST interface: angle-of-arrival (AoA) based spoofing detection, GLRT-based jamming detection and localisation, and physical-layer secret key generation, operating on measured 64-element ULA channel state information at 2.61 GHz. A live demonstrator is hosted at https://robust6g-demo.etis-lab.fr/. Provided in both JSON and YAML forms.