One thing I've noticed building with Claude Code is that it's pretty aggressive about reading .env files and config when it has access. The proxy approach sidesteps that entirely since there's nothing sensitive to find in the first place.
Wonder if the Anthropic team has considered building something like this into the sandbox itself - a secrets store that the model can "use" but never "read".
We spent the last 50 years of computer security getting to a point where we keep sensitive credentials out of the hands of humans. I guess now we have to take the next 50 years to learn the lesson that we should keep those same credentials out of the hands of LLMs as well?
I'll be sitting on the sideline eating popcorn in that case.