https://github.com/anthropic-experimental/sandbox-runtime
This is combined with "auto" mode.
Seems to work so far. I've manually checked various things, rw access, access to sensitive folders/files etc.
So far, I've only used it on two small projects. My major projects I've been clicking through prompts and recently switched to "auto" mode.
I'm not quite sure why anyone would trust "--dangerously-skip-permissions". I've seen these agents go off-piste far too many times, installing unnecessary packages, environments, calling sudo & creating files in all sorts of places.
There's a page on various sandboxing strategies on their site:
https://code.claude.com/docs/en/sandbox-environments
I've seen various comments in several topics with folk baking their own sandboxes. That's great. Although I'd be inclined to try Anthropic's solutions initially.