gistfile1.js

var asset = new Chute.API.Asset({ album: 'ALBUM_SHORTCUT', asset: 'ASSET_SHORTCUT' });

if(asset.hearted() == false) { // use hearted() method to check if asset was already hearted by this client before
  asset.heart({ success: function(){
    // asset hearted
  }});
} else {
  asset.unheart({ success: function(){
    // asset unhearted
  }});
}