A software plug-in module that interfaces to a media editing host application generates and embeds information about a media composition being edited directly within portions of the user interface generated by the host application. The information may include a custom representation of media data of a time-based element of the media composition that replaces, augments, or overlays a timeline representation of the element generated by the host application. Media editing functionality provided by the plug-in may be accessed by an operator based on viewing or interacting with the custom representation. Results of analysis of the media composition by the plug-in may be displayed within the host-generated timeline and used by an operator as a basis for performing edit operations with standard host tools or with plug-in generated tools. Plug-ins may embed their interfaces within user interfaces of host digital audio workstations, non-linear video editing systems, and music notation applications.