Definition
Plain language
An AI whose internal settings anyone can download and modify.
As stated in the literature
A model with publicly released weights, permitting local inference and fine-tuning without API access to the original provider.
Also called: open models
Why it matters: Downloadable weights let outsiders inspect, test, and modify a system independently, but they also mean any safety behavior built in can be trained back out.
For example, a researcher can download an open model's weights onto their own machine and run it offline without sending a single request to the company that made it.
Heard on the show
“Pick a model — we'll use the two-billion-parameter Gemma as the running example, that's Google's small open model — and run it through two completely separate tasks.”Episode 004 — The Sycophancy Circuit That Survives Alignment Training