The current research conducts an advanced high-order Chebyshev spectral collocation study of steady biomagnetic Au-blood nanofluid flow due to peristaltic movement of a linearly stretching plate with a localized magnetic dipole actuation effect. It accounts for the influences of wall suction, velocity slip, mixed convection, convective wall heating, viscous dissipation, Joule heating, and pyromagnetism. The blood is assumed to be the base liquid with gold nanoparticles added to the formulation via effective one-phase thermophysical properties accounting for the impact of nanoparticle inclusion on viscosity, density, specific heat, electrical conductivity, thermal conductivity, and thermal expansion. The problem is mathematically expressed in terms of coupled nonlinear partial differential equations. They are transformed into a corresponding system of ODEs, which are solved on Chebyshev–Gauss–Lobatto grid points, thus allowing exact calculation of wall gradient values for determination of the skin friction and heat transfer rates. The findings reveal that suction, slip effect, buoyant force, and larger Prandtl number accelerate hydrodynamic relaxation and suppress thermal penetration while the ferromagnetic interaction coefficient delays velocity development and elevates temperature due to the magnetization effect. Higher Biot and Eckert numbers intensify wall heat injection and enhance mechanical energy dissipation, respectively, leading to an increased thermal level. The present study reveals the interdependencies between the magnetic field, wall transpiration rate, and thermal effects that must be considered jointly when designing the wall response.