What
A subagent is a helper agent that Claude Code starts to handle part of a task, and a background subagent keeps running while you carry on. Before this release, when one failed, Claude Code handled the failure without recording that the subagent had finished.
Now, if the subagent was running and has stopped once the failure is handled, Claude Code saves a record that it finished. This covers:
- a subagent that stalls, with the message "Agent stalled: no progress for" a period of time
- an error while the subagent is wrapping up
- any other error
If saving that record itself fails, Claude Code logs a warning that it "failed to record the finish of" the subagent.
Why
A failed or stalled background subagent now leaves a saved record that it is done. This probably helps when resuming sessions or listing them, where such a subagent could otherwise look as if it were still running.