Should /specify be used for my whole web app? Or for features inside my web app? Or both? [best practice]

[infinitelyloopy-bt]

My question is should I use the /specify to articulate the whole and complete application or only specific features within the application my fear is that if I dictate the whole web application, then how would it create a plan and list of tasks? I am afraid that both the plan and list of tax are going to be huge.

Context:
Specifically, I am asking if I am about to embark on a brand new web application that has the ability to use stripe for billing and subscription management uses clerk for authentication and uses Supabase as the database and let's say it is a web application that helps users maintain food recipes as an example.