Versions & rollback
Every time you save an agent's configuration, niil captures a version — a snapshot of its model, system prompt, parameters and settings at that moment.
Review history
The Versions tab lists versions newest-first, each showing the version number, model, a preview of the system prompt, parameters and when it was captured.
Roll back
Found that a change made the agent worse? Choose Roll back on an earlier version to restore that configuration. Rolling back itself creates a new version, so nothing is ever lost — you can always move forward again.
This makes it safe to experiment: tweak the prompt, add a skill, change the model, and revert cleanly if the results regress.