Vibe coding on a boilerplate: stop your agent from rebuilding what it already has

AI coding agents often redundantly recreate existing scaffolding when working with SaaS boilerplates, leading to duplicated systems like Stripe clients and webhook routes. This issue occurs because agents may not recognize existing internal billing structures, resulting in plausible but incorrect work. Research indicates developers waste approximately 17% of AI-assisted coding time on this redundant regeneration. Improving prompts is an ineffective long-term solution, as agents continue to invent unnecessary work instead of utilizing the existing codebase.