Right now it's a python library, but the vision is to build a new framework / SDK / programming language which allows you to seamlessly mesh "plain old code" with LLM evaluations, while having a runtime which does "smart" context engineering in the background in order to steer the LLM and improve its correctness.
The end-goal is for this paradigm to enable new kinds of agentic applications, which leverage the flexibility of LLMs while retaining the determinism of regular code.