In the Spectacle screen capture utility there is now an "Annotate" button at the bottom.
It sounds like a great idea, but I still need to figure out how to use it. After taking a screenshot, I clicked on that button and expeted to see a text box where I could describe the image. Instead, I got a message saying "Annotation done."
If anyone here has figured it out, please let the rest of us know. @tomscharbach ?