Current implementation of debugging support (for plugins started via host) is unfortunately completely unusable. The way this would ideally work is that user would start neovim with $NVIM_LISP_DEBUG=filename, and every output to something like nvim:debug would write to specified file.
Also, host should catch everything being written to standard output from inside plugins in order to not break the communication with neovim.
Current implementation of debugging support (for plugins started via host) is unfortunately completely unusable. The way this would ideally work is that user would start neovim with $NVIM_LISP_DEBUG=filename, and every output to something like nvim:debug would write to specified file.
Also, host should catch everything being written to standard output from inside plugins in order to not break the communication with neovim.