The trace_irc code described in Ref.  can be downloaded here
The program can read metadynamics output files from CPMD, CP2K, and PLUMED and trace the lowest free energy pathway. A brief description is found in a README file and a list of the keywords is generate by running trace_irc.x -help. There is no manual unfortunately. In case you wish to addapt the program to read your favorite input, this should not be so hard as the C code is commented and not difficult to read. Good luck playing with it.
 A recipe for the computation of the free energy barrier and lowest free energy path of concerted reactions. Bernd Ensing, Alessandro Laio, Michele Parrinello and Michael L. Klein, J. Phys. Chem. B 109 (2005), 6676-6687 DOI: 10.1021/jp045571i
 Perspective on the reactions between F– and CH3CH2F: the free energy landscape of the E2 and SN2 reaction channels. Bernd Ensing and Michael L. Klein, Proc. Natl. Acad. Sci., USA 102 (2005), 6755-6759 DOI: 10.1073/pnas.0408094102
 Metadynamics as a tool for exploring the free energy landscape of chemical reactions. Bernd Ensing, Marco De Vivo, Zhiwei Liu, Preston Moore, and Michael L. Klein, Acc. Chem. Res. 39 (2006), 73-81 DOI: 10.1021/ar040198i