I've been doing this manually for a while and it works surprisingly well even without the initial email. I usually start with a prompt like "Write an email apologizing for not being able to make it to a meeting due to a prior engagement". You can then ask the model to edit it by adding details, making it shorter or less professional and even translate it to another language.
yes i initially was a bit of skeptical of the quality of content AI can produce but then I tried ChatGPT and it blew my mind. I find myself using it regularly now.
If I send an email to schedule a meeting, will it parse my calendar was well to infer my availability?
i haven't added any calendar integration yet.
Does it use the OpenAI instance of GPT or do you run your own?
It's not possible to run GPT now. It will never be open for self hosting despite the company's name openai.