We develop a formalism to characterize the redshift evolution of the
  dark energy potential. Our formalism makes use of quantities similar
  to the Horizon-flow parameters in inflation and is general enough
  that can deal with multiscalar quintessence scenarios, exotic matter
  components, and higher order curvature corrections to General
  Relativity.  We show how the shape of the dark energy potential can
  be recovered non parametrically using this formalism and we present
  approximations analogous to the ones relevant to slow-roll
  inflation.   Using observations of passively evolving
  galaxies and supernova data we derive constraints on the dark energy
  potential shape in the redshift range 0.1 < z < 1.8. Our findings
  show that at the 1-sigma level the potential is consistent with
  being constant, although at the same level of confidence variations
  cannot be excluded with current data. We forecast constraints
  achievable with future data from the Atacama Cosmology Telescope.