title_body: Adding blurb/summary metadata to an ebook file
upvoted_answer: Anything that you want to actually show up on an ebook reader will need to be in the content files of the epub, just like any of the chapters or other divisions of the text. It is possible to include a description in the metadata of the book; this should appear in the &lt;meta&gt; section of the content.opf file and be formatted as described in the epub 3.0 specification. That metadata will not necessarily be visible to any reading systems, but it'll be in there.
  
  Note that the &lt;dc:description&gt; element uses the Dublin Core Metadata standard, which says
  
  
    Description may include but is not limited to: an abstract, a table of
    contents, a graphical representation, or a free-text account of the
    resource.
  
  
  So while there's some room for interpretation, it's not really the place for blurbs as such, which are generally endorsements rather than "account[s] of the resource."
  
  Again: if you want it to be read by devices, just include it as another section of the manuscript.