  We find a massive simplification in the non-perturbative expression for the
structure constant of Wilson lines with 3 cusps when expressed in terms of the
key Quantum Spectral Curve quantities, namely Q-functions. Our calculation is
done for the configuration of 3 cusps lying in the same plane with arbitrary
angles in the ladders limit. This provides strong evidence that the Quantum
Spectral Curve is not only a highly efficient tool for finding the anomalous
dimensions but also encodes correlation functions with all wrapping corrections
taken into account to all orders in the `t Hooft coupling. We also show how to
study the insertions of scalars coupled to the Wilson lines and extend our
results for the spectrum and the structure constants to this case. We discuss
an OPE expansion of two cusps in terms of these states. Our results give
additional support to the Separation of Variables strategy in solving the
planar N=4 SYM theory.
