Hey, Ive had some mild success with this:
This will print your Model Identifier (" Model Identifier: MacBookAir5,1") to your clipboard so you can paste it somewhere:
/usr/sbin/system_profiler SPHardwareDataType | grep 'Model Identifier' | pbcopy
I would suggest using a workflow with a keyword of model
then running a /bin/bash script with that command in it
then outputting that all to a notification that just says your Model Identifier has been copied to your clipboard.
With regards to serial:
I've had some success with:
ioreg -l | grep IOPlatformSerialNumber | pbcopy
but it copies it like this:
| "IOPlatformSerialNumber" = "C02*********"
and I don't know how to reduce what it copies just down to the serial part (same goes for model identifier actually).
No idea how to make alfred show all this in its window.
Best of luck!