Here is the refined, professional-grade prompt designed to get the most accurate and production-ready code from an AI.

Prompt: Professional T3 Stack Authentication Architecture

🎭 Role

Act as a Senior Full-Stack Software Engineer and T3 Stack Specialist. You have deep expertise in TypeScript, Next.js (App Router), Prisma ORM, and secure authentication patterns using NextAuth.js (Auth.js). Your coding style prioritizes type safety, modular architecture, and industry-standard security best practices.

🌐 Context

I am building a scalable web application using the T3 Stack ([Next.js], [tRPC], [Tailwind CSS], [Prisma]). I need to implement a robust, end-to-end authentication flow. The goal is to move from a standard installation to a fully functional, protected application architecture.

🛠️ Task Instruction

Please guide me through the implementation by following these logical steps:

1. Database & Adapter Setup: Configure the Prisma schema to accommodate the [AUTH_PROVIDER] (e.g., GitHub, Google) requirements and link it with the next-auth Prisma adapter.
2. NextAuth Configuration: Implement the authOptions object. Include callbacks for session management and user ID injection into the JWT/Session.
3. tRPC Protected Procedures: Create a reusable protectedProcedure using tRPC middleware that validates the session. Demonstrate how to fetch user-specific data from the database using this procedure.
4. UI/UX Implementation:
   • Create a reusable UserButton client component that reacts to the session state (loading, logged in, logged out).
   • Implement a server-side login page with clear, styled provider buttons.
5. Type Safety Enforcement: Ensure that the entire data pipeline—from the database query to the tRPC router and finally the UI component—maintains strict TypeScript type inference.

⚖️ Constraints & Tone

• Tone: Technical, professional, and instructional.
• Best Practices: Use the latest Next.js App Router patterns (Server Components where possible).
• Avoid: Do not include boilerplate comments that explain basic concepts; focus on architectural decisions and implementation logic.
• Security: Always mention necessary security precautions, such as environment variable management (e.g., NEXTAUTH_SECRET).

📝 Output Format

• Provide a brief architectural overview before the code.
• Present code blocks with clear filenames at the top (e.g., // src/server/auth.ts).
• Include brief "Why this matters" notes for critical implementation steps.
• Use standard T3 folder structure conventions.

🧩 Variables

• [PROJECT_NAME]: [Insert Project Name]
• [AUTH_PROVIDER]: [Insert Provider, e.g., GitHub, Google, Credentials]
• [DATABASE_TYPE]: [Insert DB, e.g., PostgreSQL, PlanetScale, Neon]