What changed: Background conversation-history prefetching is now active for CCR (cloud session relay) sessions. Claude Code proactively loads recent events for background sessions so that attaching to them feels instant.
Details
- Prefetch is keyed by CCR session ID, validated against the session ID format before proceeding.
- Results are cached on disk under a
cc-history-prefetch-key. - Gracefully degrades: gate failures, HTTP errors, and parse failures are all logged but do not block session attach.
Evidence
History prefetch system (search for "[historyPrefetch]")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.