Open an the .sch file in Eagle, and run one of the scripts from the File->Script dialog.
Alternatively, copy the scripts into the Eagle/ulp directory and run them from the command-line:
$ cd .solderpad $ eagle -C'RUN bom-json.ulp; QUIT;' ../myproject.sch
You might also like to generate the schematic and board images from the command-line:
$ eagle -C'EXPORT IMAGE schematic.png 600;QUIT' ../*sch $ eagle -C'EXPORT IMAGE board.png 600;QUIT' ../*brd
It's possible to incorporate these scripts into Makefile or run as a git hook so the export is run automatically beofore pushing to SolderPad.