{"version":"2.1.281","anchor":"sandbox-prompt-new-macos-guidance-for-local-port-binding-an","canonical_anchor":"sandbox-prompt-new-macos-guidance-for-local-port-binding-an","heading":"Sandbox prompt: new macOS guidance for local port binding and open\/osascript","tier":"notice","area":"Sandbox","url":"https:\/\/changelogs.core-directive.com\/v\/2.1.281\/e\/sandbox-prompt-new-macos-guidance-for-local-port-binding-an","release_url":"https:\/\/changelogs.core-directive.com\/v\/2.1.281","markdown":"### Sandbox prompt: new macOS guidance for local port binding and open\/osascript\n\nOn macOS, Claude is now told how to recognise sandbox blocks on local ports and on open\/osascript, and what to offer the user instead\n\n**Unclear.** The finding says the `\/sandbox exclude` and `!` suggestions appear only in a \"non-auto\" branch but does not say what that mode is.\n\n**What**\n\nThe sandbox is a restricted environment that shell commands run inside, limiting what they can reach. Claude receives written instructions about it, and those instructions now include two paragraphs that only apply on macOS:\n\n- Local port binding: this applies when a network proxy is configured and local binding is turned off. An `EPERM` error from bind or listen (the calls a program makes to open a port on your machine) means the sandbox blocked it. Claude can tell you to set `sandbox.network.allowLocalBinding: true`, which takes effect without a restart. In one variant of the instructions it can also suggest `\/sandbox exclude <pattern>` or running the command yourself with the `!` prefix.\n\n- `open` and `osascript`: these are blocked when `allowAppleEvents` is not set to true, and Claude is told not to retry them with `dangerouslyDisableSandbox: true`.\n\n**Why**\n\nOn a Mac, a local dev server that fails to start should now come with an explanation and a specific setting to change, instead of a bare permission error. Commands that open apps or run AppleScript will not be quietly retried outside the sandbox.\n\n- Area: Sandbox\n- Tier: You'll notice\n- Useful: 2\/5\n- Signal: 2\/5"}