We already have AI agents that can ask a human for help / clarification in those cases.
It could also analyze the company website, marketing materials, and so forth, and use that to infer the missing pieces. (Again, something that exists today)
If the AI has to ask for clarification, you can’t run it as a reproducible build step as envisaged. It’s as if your compiler would pause to ask clarifying questions on each CI run.
If the company website, marketing materials, and so forth become part of the input, you’ll have to put those in version control as well, as any change is likely to result in a different application being generated (which may or may not be what you want).
It could also analyze the company website, marketing materials, and so forth, and use that to infer the missing pieces. (Again, something that exists today)