A system includes a media optimizer that adaptively generates and transmits a modified manifest file based on an original manifest file corresponding to an associated media asset from a content provider in response to a media content request from a client for the associated media asset. The original manifest file specifies bitrates. The media optimizer extracts parameters associated with the media content request and applies bitrate policies based on the extracted parameters to adaptively modify the original manifest file to generate the modified manifest file. The media optimizer is further configured to transmit the modified manifest file to the client for selection by the client of a bitrate associated with delivery of the associated media asset.