MessyBrainz is a MetaBrainz project to support unclean metadata. While MusicBrainz is designed to link clean metadata to stable identifiers, there is a need to identify unclean or misspelled data as well. MessyBrainz provides identifiers to unclean metadata, and where possible, links it to stable MusicBrainz identifiers.
MessyBrainz is currently used in support of ListenBrainz. Submission to MessyBrainz is restricted, however the resulting data will be made freely available.