Yeah, the underlying sandbox technology between Ash and CC is fundamentally different.

Ash is built on the Endpoint Security and Network Extension APIs. Together, they cover the full gamut of potential sandbox escapes, and it's a simple process to update sandbox rules while the sandboxed process is running.

Claude Code sandbox is built mainly on sandbox-exec, an older macOS sandbox technology. It works for filesystem and IO device control, but it can only filter network requests by IP address. CC uses an application-level network proxy as a workaround, but not every network client respects the HTTP_PROXY env variable it requires. There are other workarounds in CC sandbox for complex use cases (e.g. dangerouslyDisableSandbox) that Ash does not need.