Example of outlier in CIGALE-based analyses from the 10^{43 − 44} erg/s AGN luminosity bin. Panel (a) shows the original COSMOS data (CosmosId: 420968 at z = 0.33), where a M_⋆ = 10⁸ M_⊙ galaxy-only model (black) reproduces the observed fluxes (purple) with small residuals (χ_red² = 0.4). Panels (b), (c) and (d) present CIGALE fit to the Chimera fluxes (purple) with D14, C15 and Y19 settings. In all three models, the galaxy template is incorrectly placed at 10³⁶ W instead of < 10³⁵ W as in panel (a). In the C15 and Y19 models, the best-fit model is dominated by the AGN component (orange). The bottom panel (e) shows the fit by GRAHSP for the same object. The galaxy component has very large uncertainties (purple shade at the bottom), but includes the true stellar contribution (compare the purple curve here to the black curve in the top left panel). The error budget has slightly increased during the analysis from the blue error bars with wider caps to those with thin caps. The power-law AGN model (blue) dominates the fit at all wavelengths.