The relation between the low energy constants appearing in the effective field theory (EFT) description of the λN → NN transition potential and the parameters of the one-meson-exchange model previously developed is obtained. We extract the relative importance of the different exchange mechanisms included in the meson picture by means of a comparison to the corresponding operational structures appearing in the EFT approach. Constraints on weak baryon-baryon-meson couplings for a possible scalar exchange are also discussed. This work is based on the lowest order EFT approach of Ref. [1]. Higher order contributions are sketched.