I’m generating a complete post and would like the engine creates bullets when needed.
A trailing ‘-’ in the prompt helps.
The engine creates completions based on prompt. Another way to say this is that completions are heavily influenced by prompt.
So, being specific within the prompt helps.
E.g you can alter your prompt to portray what you want by adding
"use bullets/points to make it concise" to your prompt.
Also, as @vaibhav.garg mentioned, adding ‘-’ should help prompt the engine to generate bullets.
You can read more about prompt design here: OpenAI API