In addition to the project you mentioned, there is quite an ecosystem for Emacs working with API-based LLM:
https://github.com/emacs-openai/chatgpt
https://github.com/stuhlmueller/gpt.el
https://github.com/rksm/org-ai
https://github.com/emacs-openai/chatgpt
https://github.com/stuhlmueller/gpt.el
https://github.com/rksm/org-ai