<p>Optimising the complex machinability phenomena of Wire-cut Electric Discharge Machining (WEDM) is always a concern for industry when its requirements involve multiple quality factors, such as surface roughness, kerf width, and recast layer thickness, while maintaining considerable material removal rates. Surface defects, discharge environmental contamination, and inclusions are also major concerns for such versatile, non-traditional machining. During the profile cutting of tool steel like HSS-M42, a high-temperature strength alloy, it suffers from limitations, including slow machining rates, poor surface finish, and the formation of recast layers with microdefects. Furthermore, the surface integrity across the WEDM cut-section also varies. An effective integrated fuzzy-PSO hybrid technique has been developed to address these challenges and improve performance, particularly in cutting tool production. The influence of process parameters on these responses was initially investigated. The best surface quality obtained through the hybrid algorithm was further analysed using SEM and EDX, revealing the presence of foreign elemental inclusions, such as oxygen, carbon, copper, and zinc, on the machined surface.</p>