Online searches leads me to think these are Spicebush Swallowtail Caterpillars. The color (brown not green) and behavior (daytime eating not daytime sleeping) doesn’t exactly match what I’ve read and I’d be happy to have any input.
The false “eyespots,” presumed to scare off predators are correct for the Spicebush Swallowtail.
The caterpillar’s real eyes are pinpoint size and somewhere near the mouth.
These caterpillars could be known as “eating machines” which is how I happened to notice them as previously robust plants are now sticks.
I don’t know if these patio pots have enough acceptable foliage to support the five caterpillars I saw to their next stage. I’ll look for them again tomorrow.