Are they damaging your plant? If not, no big deal. If yes, they are cats, and Bt should take care of them.

The plant has struggled to grow in general. Finally I see it growing and then spotted ants + these bugs..Bt is Bacillus Thuringiensis ?

They aren't caterpillars. They have segments, legs and antennae. They look like millipedes since they have two pairs of legs per segment. They mostly eat decaying organic matter.

OK, so it isn't clear that these things are eating your plants. We're talking pieces chopped out of leaves, not failure to thrive.

Caterpillars DO have antennae. Usually small ones. Wow. I sure can't see the number of legs per segment in this tiny picture. Caterpillars certainly can have segmented bodies.

" They mostly eat decaying organic matter. " Ok so then it is probably eating away the plant-food which was just put down a week back? Thank you all for responding.