The practical reason for 4.0.1 is simple: after v4.0.0 was published, main received one more public fix. Git installs following main could receive that state through nexo update, while the published release tag, npm package, and website still described the earlier snapshot. That is the kind of drift that creates operator doubt, even when the code itself is fine.
What 4.0.1 actually changes
- It packages the post-
v4.0.0mainline fix as a real patch release instead of leaving it implicit inmain. - It adds a correction-aware
LEARNING REMINDERintools_sessionswhen an operator clearly corrects the agent and no recent learning capture appears nearby. - It updates the public release surfaces so git installs, npm, GitHub Releases, and the website describe the same shipped state again.
What it does not change
4.0.1 does not walk back the broader 4.0.0 memory release. Multimodal refs, pre-compaction auto-flush, the public claim wiki, readable memory export, richer inspectable user-state adaptation, and public retrieval/backend controls remain the core product story of the 4.0 line.
Why the reminder matters
NEXO already had protocol tools for learnings, but that still left a small discipline gap: a user correction could be visible in the session without producing a durable learning. The new heartbeat reminder is a narrow but useful fix. It does not invent a learning on its own. It simply makes the omission harder to ignore while the correction is still fresh.
If you want the complete 4.0 memory-surface story, read the 4.0.0 article. If you want the exact public release record, open the 4.0.1 changelog section.