  We study the X-ray irradiation and likely photoevaporation of the three
planets around the star K2-136. These are the Earth-sized K2-136 b, the
mini-Neptune K2-136 c, and the super-Earth K2-136 d. XMM-Newton observations of
the star indicate an X-ray luminosity of $(1.18\pm0.1)\times10^{28}$ erg
s$^{-1}$ in the range 0.15 to 2.4 keV, resulting in an activity of $L_X/L_{\rm
bol}=(1.80\pm0.68)\times10^{-5}$. The evaporation past of the planets were
modelled using the XUV stellar tracks by Johnstone et al. (2021), the energy
limited mass loss formulation (Lecavelier des Etangs et al. 2007, Erkaev et al.
2007), and the thermal evolution formulation by Lopez & Fortney (2014). Our
results suggest that planets b and d are most probably purely rocky and have
been stripped of their envelopes. On the other hand, planet c likely still has
an envelope consisting of 0.8% of the total mass, with its core being
relatively large (2.3 $R_{\rm E}$).
