Summary

Please make it clear that setting --size medium will download JPEG images, and more generally the expected consequent of all the sizes. For example I have found that --size adjusted will download the HEIC in the correct crop as set by the camera. Having full documentation on these features would save a lot of time.
It's amazing that this tool can provide all of this! Thank you.

Context

I would like to download my iCloud Photos images from iCloud so as to free up storage and can see that the original files do not contain enough metadata to fully reproduce JPEG images in the correct crop etc. Having the JPEG images downloaded as well is the only way I can see to have a complete set of images.
There are many other details which are not obvious to me as a layperson, such as where the metadata is stored, if it can be embedded in images for example. I would so appreciate greater detail in your documentation as to what file types are supported, what metadata can be associated or is associated, and what is missing. It seems that Apple holds a lot of data back requiring downloading of secondary artifacts to get to - for example JPEG or adjusted images.

Going down the rabbit hole: What can we know about HDR in images? Is all the data available in an HEIC? Can we get other information such as detected objects or people?

Thank you for your amazing work!