On the Smart Podcast Player, you can manually add a hashtag (or multiple hashtags separated by commas) to the prepopulated tweet.
For customized social sharing via the shortcode builder, click here.
Entering a Hashtag Manually
Add the following to your shortcode (no # required):
My player shortcode now reads:
[smart_podcast_player url="http://www.soundcloud.com/askpat/" hashtag="AskPat"]