Are you sure? When they announced it they said they will update quotas to account for it. Which just means that the next adjustment will effectively null it out.

The docs all say there is a time and billing cost:

> Auto mode may have a small impact on token consumption, cost, and latency for tool calls. https://claude.com/resources/articles/auto-mode#what-to-expe...

https://code.claude.com/docs/en/permission-modes#cost-and-la... doesn't say anything specific. It mentions that server-side classification can be used but doesn't talk about the billing for it.

But at the end of the day it is a leaky system. It may reduce the frequency of bad actions but doesn't prevent it. So you need the sandbox either way.