What
This affects files attached to messages that reach a session through a remote connection.
- Missing checksum: some attachments arrive without a sha256 checksum, a fingerprint used to confirm the file is intact. Claude Code now counts these and adds a note about them to the start of the prompt.
- Delivery count: Claude Code now records how many attachments were actually delivered.
- Early downloads: Claude Code can download an attachment before it is needed, which is called prefetching. These early copies used to expire on a fixed timer. They can now also be dropped when they go unused, or refused early.
- Requests: downloads of prefetched files send an extra header, and attachment uploads now identify Claude Code as the sender.
Why
Attachments sent from elsewhere are delivered more reliably. When one is not delivered or cannot be verified, that is now easier to see.
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubt
The exact wording of the new prompt note and the purpose of the extra download header are not known.