Single active session policy logs out other devices with no warning

Problem

When signing into Claude Code CLI on a second device using the same account, the first device is silently logged out. There is no warning before this happens and no indication on the logged-out device of why the session ended.

Context

This is disruptive for a single developer working across two machines on different OSS projects simultaneously. For example: running a docker compose environment for one project on one laptop while browsing a second OSS project on another. Switching to the second laptop to check on a project should not kill the session — and potentially disrupt the running environment — on the first.

This is a single user working legitimately across two devices, not a team attempting to share an account.

Suggested improvement

• Support concurrent sessions per account for a single user, or
• At minimum, warn the user on the new device that signing in will terminate the existing session on other devices, so they can make an informed choice before proceeding

Impact

Poor UX for developers who routinely work across multiple machines — a very common workflow.