We present a plugin implementation for the multi-platform WaveSurfer sound editor. Added functionalities are the semi-automatic extraction of beats at diverse levels of the metrical hierarchy as well as uploading and downloading functionalities to a music metadata database. It is built upon existing open source (GPL-licenced) audio processing tools, namely WaveSurfer, BeatRoot and CLAM, in the intent to expand the scope of those softwares. It is therefore also provided as GPL code with the explicit goal that researchers in the audio processing community can freely use and improve it. We provide technical details of the implementation as well as practical use cases. We also motivate the use of rhythmic metadata in Music Information Retrieval scenarios.