Feature importance evaluation for M-type synthetic models in the test set using Settl-Net. We present the median flux of M-type class III template stars in the first row. The grey area indicates the interquantile range between the 25 and 75% quantiles. The other three rows show the feature importance across the wavelength for each stellar parameter. Vertical lines and shades indicate the location of typical tracers of stellar parameters listed in Table 5.