Could be birds.

tj

The peas inside are gone, and birds and animals will be after the peas. Not insects. 3-4 feet off the ground is a challenge for small animals, especially for not pulling down vines, however, so birds sound like a good guess. In fact, if pods closer to the ground are untouched, it's birds for sure.

That is so weird, we've never had a bird problem with our peas but those "bites" do resemble the shape of a sharp beak.

If you put peas out in a bird feeder, they'll quickly disappear. Peas are seeds, and birds eat seeds.

I came to the right place.

A few minutes ago, I looked outside and saw a northern cardinal active within the top several inches of foliage. I walked out to see if I could spot any damage at that location. As I approached the vines, I saw a second cardinal emerging from deep within the foliage. A quick look did not turn up any evidence of new damage, but I think it’s the cardinals.

So far, it’s tolerable and manageable without any intervention.

Good analysis from Dan

I am guessing birds too