Further information on setting up the notification in Codebase can be found here.
To integrate with Prowl, you need to retrieve the API token from your account. Navigate to the API Keys tab initially:
Under the Generate a new API key area, type a memorable note, and click Generate Key to save it.
You will now see the newly generated key under the Current API keys:
Just copy the API Key into the field of the same name in Codebase, and choose your notification priority.