Currently, on a fetch failure in metatools master, output looks like this:
[ERROR 19:33:37] Fetch error: (<metatools.fastpull.spider.FetchRequest object at 0x7fe9c3229f10>, 'HTTP fetch_stream Error 404: <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">\n<html><head>\n<title>404 Not Found</title>\n</head><body>\n<h1>Not Found')
Ideally, this should also supply information about the autogen and package that this fetch was associated with, and URL.