As discussed in the forums, dev-db/mysqltool was removed from portage recently. It appears that this package is no longer being maintained. I've been using this package for quite some time, and have had no problems with it.
Just because it's no longer maintained upstream doesn't mean it's suddenly broken. Can't we leave it in Portage, perhaps with a warning when installing it that it is unsupported?
We won't be maintaining stuff that is dead upstream, sorry.
It's not a matter of maintaining the package. It's a matter of leaving the ebuild for people who want to use it.
Perhaps it should be moved from dev-db to misc-unsupported or something like that. Or at least wait until there's a bug reported that should be fixed upstream to pull it (I didn't see any such reports in the database).
I just don't see why something that is working perfectly needs to be removed.
Feel free to grab it and use in your overlay, we won't be keeping stuff that we cannot maintain in the tree.