When the container Claude Code runs in (the isolated environment hosting the session) restarts, Claude now gets a system reminder. A system reminder is a note Claude Code adds to the conversation for the model to read. It lists:
Stopped tasks: background tasks the restart cut off.
Undelivered results: tasks that finished before the restart but whose results never reached Claude.
Where they are known, it also gives each task's output file.
Why
Claude learns that work was lost or went unreported, and knows where to look for output, instead of carrying on as if those tasks were still running or had never finished.
