Change working directory in a live session

[lifeizhou-ap]

We are working on Goose, where users can change the primary working directory of a live session through the Goose-specific unstable ACP method _goose/unstable/session/working-dir/update. After the update, subsequent agent operations use the new directory as their working context, while the session ID and conversation history are preserved.

We noticed that the completed Session Info Update RFD states that "cwd is immutable and set during session/new." Would ACP be open to an optional capability that lets clients change it without requiring users to start a new session?