Under the hoodTier: how much it should matter to you
3Useful: my rating, 1 to 5
3Signal: worth watching, 1 to 5
SDKArea: what it touches
Internal ChangesKind: in v2.1.281,
Internal ChangesSection of the release
What
Claude Code can now be started as a spare: a process that is already running and ready, parked until a program using the SDK hands it a session with a claim_session request. This is controlled by a hidden --await-claim flag, a command-line option not listed in the help.
Two new launch values track this:
spareClaimState, which is parked, claiming, claimed or failed, and resets to none
spareParkedAtMs, the time the process was parked
Why
A host program can keep a ready process waiting, so a new session does not have to wait for Claude Code to start up from scratch.
