Rose Picker uses Rose code (which has to be copied into the repository since we can't easily import it from Git) to read the metadata file and converts it into an intermediate JSON file. This can be read by the LFRic configuration reading code generator scripts without mixing licenses.
These tools can be installed in the usual way using pip install ..
LFRic is distributed under the BSD 3-Clause license, while the Rose tool is released under the GPL license. As Rose Picker incorporates code from Rose, it must comply with the GPL licensing terms.