Ask HN: How do you compose your long LLM prompts?

Usually, I just write mine directly in the tool I'm using (chatGPT, claude, etc). However, I've found this workflow lacking when writing a long prompt that describes a product/engineer spec as the built-in text boxes are small and I often hit "enter" before I'm ready.

I've tried using a separate text editor or google docs sheet to compose these long prompts which works but still feels clunky and inefficient.

I'm curious to hear what people's workflows look like.