Hook or event for updating tags programmatically?

[BoPeng]

My JLab extension jupyterlab-sos uses a few tags to control the generation of HTML reports. Currently it adds tags and removes tags using keyboard shortcuts. However, the changes are done under the hood and are not reflected in the side panel when this extension is installed.

Is there any event or hook so that my extension can notify jupyterleb-celltags changes of cell meta data? It might be easier to use this extension to add/remove tags, but I do not know if an API is provided.