A study of 2,430 Claude Code interactions across real repositories reveals that the AI coding assistant strongly prefers building custom solutions over recommending third-party tools — appearing as the top choice in 12 of 20 categories. When it does pick tools, choices are decisive: GitHub Actions (94%), Stripe (91%), shadcn/ui (90%). Deployment is stack-determined: Vercel for JS, Railway for Python, with traditional cloud providers getting zero primary picks. Significant generational shifts exist between model versions, notably Prisma→Drizzle for JS ORM, Celery→FastAPI BackgroundTasks for Python jobs, and Redis→Custom/DIY for caching in newer models.