You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
2Signal: worth watching, 1 to 5
SendMessageArea: what it touches
ImprovementsKind: in v2.1.286,
ImprovementsSection of the release
What
SendMessage is the tool Claude uses to send messages, and sometimes files, to another Claude Code session. Whether a file may go to a session on another machine used to be decided once by a fixed check. It is now checked three times:
before asking you for permission
again after you answer
again just before the file is sent
When the cause is a residency restriction or the file-sending switch allow_send_file is off, the refusal uses the standard message. Otherwise it reads: Cross-machine file transfer is unavailable: <reason> Same-machine (uds:) transfers still work.
Why
A refusal now tells you the actual reason and that sending to a session on the same machine still works. A policy change that happens while you are answering the permission prompt is also caught before the file goes out.
How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtWhat `allow_send_file` falls back to when the server sends nothing is not known.
