Comment by bambax
It is indeed a working demo, hitting
https://llm.koomen.dev/v1/chat/completions
More seriously, I think the reason companies don't want to expose the system prompt is because they want to keep some of the magic alive. Once most people understand that the universal interface to AI is text prompts, then all that will remain is the models themselves.
That's right. llm.koomen.dev is a cloudflare worker that forwards requests to openai. I was a little worried about getting DDOSed but so far that hasn't been an issue, and the tokens are ridiculously cheap.