The following is an example of how you can use the wp-pear-debug plugin to debug your shortcodes and posts.
If you didn't already know the plugin allows you to output anything to the debugger by using the following within your wordpress post:
This is my wordpress post with random information
Will not appear in actual post ->[wp_pear_debug]foo bar[/wp_pear_debug]
Will not appear in actual post ->[wp_pear_debug foo="bar" foo1="bar2"]
More random information in my sample wordpress post.
The above shortcodes will yield the following results:
