Comment by Fishkins

1 day ago

I agree with most of this, with one important exception: you should have some form of sandboxing in place before running any local AI agent. The easiest way to do that is with .claude/settings.json[0].

This is important no matter how experienced you are, but arguable the most important when you don't know what you're doing.

0: or if you don't want to learn about that, you can use Claude Code Web

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Fishkins

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gawa  1 day ago

The part about permissions with settings.json [0] is laughable. Are we really supposed to list all potential variations of harmful commands? In addition to the `Bash(cat ./.env)`, we would also need to add `Bash(cat .env)`, Bash(tail ./.env)`, Bash(tail .env)`, `Bash(head ./.env)`, `Bash(sed '' ./.env)`, and countless others... while at the same time we allow something like `npm` to run?

I know the deny list is only for automatically denying, and that non-explicitly allowed command will pause, waiting for user input confirmation. But still it reminds me of the rationale the author of the Pi harness [1] gave to explain why there will be no permission feature built-in in Pi (emphasis mine):

> If you look at the security measures in other coding agents, *they're mostly security theater*. As soon as your agent can write code and run code, it's pretty much game over. [...] If you're uncomfortable with full access, run pi inside a container or use a different tool if you need (faux) guardrails.

As you mentioned, this is a big feature of Claude Code Web (or Codex/Antigravity or whatever equivalent of other companies): they handle the sand-boxing.

[0] https://blog.dailydoseofds.com/i/191853914/settingsjson-perm...

[1] https://mariozechner.at/posts/2025-11-30-pi-coding-agent/#to...

sroussey  1 day ago

Do people really run claude and other clis like this outside a container??

  • kelnos  15 hours ago

    Yes. I don't bother with that. I feel like the risk of Claude Code running amok is pretty low, and I don't have it do long-running tasks that exceeds my desire to monitor it. (Not because I'm worried about it breaking things, it's just I don't use the tool in that way.)

  • kenforthewin  1 day ago

    Let's not fool ourselves here. If a security feature adds any amount of friction at all, and there's a simple way to disable it, users will choose to do so.

  • Fishkins  1 day ago

    I'm sure most folks run Claude without isolation or sandboxing. It's a terrible idea, but even most professional software developers don't think much about security.

    There many decent options (cloud VMs, local VMs, Docker, the built-in sandboxing). My point is just that folks should research and set up at least one of them before running an agent.

  • matheusmoreira  1 day ago

    How did you contain Claude Code? Did you virtualize it? I just set up a simple firejail script for it. Not completely sure if it's enough but it's at least something.