What
When a cloud session sends your machine a bundle of file changes, Claude Code now unpacks it into a throwaway directory first and checks it end to end before letting any of it into the repository. A bundle that does not match what it claims to contain is refused whole.
Details
- The bundle is indexed with
index-pack --strictinto a per-run quarantine directory, then verified four ways: every tip it names must be a commit the bundle actually delivered, the stated commit range must name exactly the objects carried, and anything it depends on must be history this side already has. - A record of the delivered object ids is written before the bundle is moved into permanent storage, so a half-applied transfer is detectable later.
- Failures produce one fixed reason rather than a per-check message, and the quarantine is swept. Stale quarantine directories, leftover
.keepfiles and orphaned delivery records are cleaned up on subsequent runs. - Part of the git sync engine; there is no separate switch for the audit.
Evidence
the pack was refused: malformed, not self-contained, or not exactly what its range names
Strings lifted out of the shipped bundle, so the claim above can be checked against them.