Checkpoints & resume
Sessions are ephemeral, but their work doesn’t have to be. Checkpoints capture session state durably so a run can outlive the machine it ran on.
What a checkpoint captures
Section titled “What a checkpoint captures”After every completed agent turn, the platform snapshots the session
workspace — the working tree, including git state and untracked files, minus
build artifacts like node_modules — into a compressed archive in durable
storage. Retention and size caps are in the
limits reference.
Resume
Section titled “Resume”Replying in a session’s thread resumes it through the first tier that
applies: if the machine is still claimed, the session re-attaches in place
with full working state; if the machine is gone, the last consistent
checkpoint restores onto a fresh machine. In Slack, !resume opens a picker
of recent sessions. The full contract — and its boundary: a session is
resumable whenever a checkpoint exists and it wasn’t explicitly released —
is in the lifecycle reference.
Next steps
Section titled “Next steps”- Session lifecycle reference — resume tiers, timeouts, failure modes.
- Limits — checkpoint retention and size caps.
this page as markdown: /sessions/concepts/checkpoints-and-resume.md· index for agents: /llms.txt