In the past the Apple Care package included a 'tools' software disk.
But as far as I know that was changed sometime ago.
It was diagnostic tools that you could run before taking/sending the unit back to Apple.
I just opened my brand new Apple Care package that I bought with my new iMac.
Nothing in there but two booklets.
On the package it says " AUTO ENROLL " so I checked online and sure enough the Apple Care registered to the iMac when I purchased it.
Even that is a change, the last time I did it you had to do the enrollment online yourself.
I'm good until February 14, 2015 !
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In the past they included a disk that you could boot from to run Hardware Diagnostic Tools.
If you called for support they would ask you to run some tests from what I recall.