Lenny

Vets whether to build a feature from scratch, use an existing free/open-source solution, or pay for a third-party API/service. Use this whenever the user asks Claude to implement, add, integrate, or write code for a feature or capability, especially one that sounds like it could already be a solved problem (auth, payments, scraping, animation, comment/DM automation, video/image generation, search, notifications, etc.), even if the user doesn't explicitly ask "should I build or buy this." Make sure to trigger this before writing non-trivial implementation code for any feature-level capability, not just when the user asks about libraries directly.

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