From what I remember, the key differentiating features were:

- a heartbeat, so it was able to 'think'/work throughout the day, even if you weren't interacting with it - a clever and simple way to retain 'memory' across sessions (though maybe claude code has this now) - a 'soul' text file, which isn't necessarily innovative in itself, but the ability for the agent to edit its own configuration on the fly is pretty neat

Oh, and it's open source