How to inspect the sandbox and debug

You might be wondering… if this is not a Docker container, how can you see what’s going on inside Docker!? How to debug/install things?

That’s quite straightforward.

You first need to run:

sbx ls

Note down the name of the sandbox for the agent you ran, e.g. ralph-claude-my-app-a1b2c3d4. Ralph also prints this name when it starts.

And then you can run bash into any of the sandboxes like so:

sbx exec -it <sandbox-name> bash # e.g. sbx exec -it ralph-claude-my-app-a1b2c3d4 bash

And you have full control over the sandbox, just like a regular container. You can install packages, run commands, etc.

You can also run the agent CLI inside the sandbox (make sure to navigate to the project directory first).

sbx exec -it <sandbox-name> bash
cd /path/to/your/project # this is the same path as the path in the root machine, e.g. /Users/your-username/Documents/your-project
claude # or codex, copilot, cursor, gemini, opencode

Re-running ./ralph.sh, ./ralph.sh --login, or ./ralph.sh --ports is safe at any point — Ralph probes sbx ls and emits sbx run --name ... <agent> . only when the sandbox doesn’t exist yet, and sbx run <sandbox-name> to reattach afterwards. The first form is create-only and would otherwise error with --name can only be used when creating a new sandbox. See RALPH.md for the full lifecycle.