Hi -- thanks for the kind words. While right now the engine only works with OpenAI, swapping out other LLMs simply from the envars is on the roadmap. Since we use Langchain for LLM calls this logic is already abstracted away so it will be a small code change.
We have some samples (including a quickstart in the README and docs https://dataherald.readthedocs.io/en/latest/quickstart.html) but will be adding more tutorials in the coming days.