Request for Support of /completions API Style

[BaiMoHan]

Currently, the API supports the OpenAI format of /chat/completions, but I would like to request support for the /completions API style as well. Custom prompts are a common requirement, and although there is a way to implement the llm.LLM interface, I have noticed that significant changes are required after each version upgrade(0.10.1->0.10.2).

Having an official implementation or related documentation for the /completions API style would be immensely beneficial. It would simplify the process and help users like me minimize the adjustments needed with each update. https://platform.openai.com/docs/api-reference/completions