You need to be very careful about using both Bridge and LrC to add metadata. If you add a star rating to a file in Bridge you can transfer it by selecting those image files in LrC and then in the Library module go to menu item Metadata> Read Metadata from File. The issue is that all other metadata and edits previously added from inside LrC will be over-written and lost! To prevent this from happening you need to first use CTRL + S (Save Metadata to File) from inside LrC before making any changes inside Bridge. Raw files will have XMP sidecar files created when you use CTRL + S in LrC and all other files (DNG, JPEG, TIFF) will have the metadata written inside the file. That metadata will then appear inside Bridge and can be edited.
As long as you understand this limitation you can successfully use both applications for metadata editing.