grunt-notify

Grunt notify: https://github.com/dylang/grunt-notify is great. However, it seems a bit limited. As far as I can tell all my messages need to be pre-generated. So the first question is how can I generate notifications? Next, It seems that grunt notify triggers based on error or success of some task. I guess based on std in/out/err? The problem where this breaks down is if some task doesn't use these. grunt compass doesn't use stderr if there are compile errors. So how can I run grunt notify when it has an error? This then leads to the next question. How can I grab the console output or stderr