Transmission spectroscopic metric in the J magnitude as a function of the planetary equilibrium temperature. The TSM values are shown relatively to the TOI-269 b (eccentricity-corrected) reference value of . Only planets orbiting M dwarf (T_eff ≤ 3875 [K]) and with R_p ≤ 5 R_⊕ were selected. TOI-269 b is shown as a black circle. The black arrow shows the range of equilibrium temperature depending on planet position during the orbit. The crosses show the locations of the orbital average, the semi-major axis, and the primary transit. Other planets with and without measured masses are shown in dark gray and light gray, respectively.