After some drive juggling [cloning to HFS+ then re-cloning back] to fix an error on my APFS boot drive, I'm now in the position where I no longer have any partition with a Recovery volume.
Carbon Copy Cloner offered to create one when I first made the clone, but as I was squeezing this into a tight space on a drive with several partitions on it already, including one with an MBR wrapper, the operation failed.
Due to further, unforeseen issues, I also had to sacrifice my Time Machine drive, so I now have no direct source to copy a Recovery Partition from.
I'm on a Mac Pro 4,1/5,1 macOS 10.13.5, which will not boot to Internet Recovery.
Is there any way to create one, hopefully without reinstalling the OS?
Alternatively, will running the OS installer directly from the App Store "live" [ie launching it from the running Finder] over the top of the existing OS do the trick?
I will, at that point, have 2 bootable OS partitions on 2 separate drives, so potentially I could run the update to one from the other, if that will gain anything.
There are many previous questions on Ask Different regarding this, but none recent enough to cover APFS.