Reconstruction of the dark energy equation of state w(z) from mock DESI BAO DR2 and DESY5 samples. The blue dashed–dotted line shows the fiducial CPL model used to generate the mocks. The red solid line represents the mean ANN reconstruction, with the dark- and light-red shaded regions indicating the 1σ and 2σ confidence intervals, respectively. The gray dashed line denotes ΛCDM with w = −1. The blue shaded bands show the corresponding 1σ and 2σ MCMC constraints. Mock uncertainties are scaled to 75% of the real data.