You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
3Signal: worth watching, 1 to 5
PreviewArea: what it touches
ImprovementsKind: in v2.1.315,
ImprovementsSection of the release
What
A preview tunnel is a connection that lets a hosted session reach a program running on a port, which is a numbered channel a program listens on. Two things changed:
When a status check probes a valid port that is not on the tunnel's list (between 1024 and 65535), Claude Code now reports it.
A new option makes the tunnel refuse requests from other sessions, insist on strict checking of secure (TLS) connections, and shut down with the reason policy if the session changes when the tunnel reconnects.
Before, the tunnel refused other sessions only when a tool server was attached to it.
Why
A tunnel can now be tied to one session, so another session cannot reach it through the same connection.
