Calibration of the numerical stability threshold employed in ARDENT. This plot results from short and long numerical integrations on three sets of systems, differing from each other with the eccentricity of the outer CJ. The relative amounts of FP and FN are shown for all sets combined, and for a various range of threshold drifts in semi-major axis Δa_max indicated by the colorbar. The diamond symbol corresponds to the default ARDENT value of Δa_max = 0.025%. This conservative choice favours minimising the amount of FN.