clade-architecture-variants

# Claude Architecture Variants ## Overview Five architecture patterns for Claude-powered applications: Chatbot (stateless API wrapper), RAG (retrieval-augmented generation with vector search), Agent (tool use loop), Content Pipeline (batch processing), and Evaluation (using Claude as a judge). Each includes complete code and a comparison table. ## 1. Chatbot (Stateless API Wrapper) Simplest pattern — proxy Claude with a system prompt. ```typescript // api/chat.ts export async function POST(req: Request) { const { messages } = await req.json(); const response = await client.messages.create({ model: 'claude-sonnet-4-20250514', max_tokens: 2048, system: 'You are a helpful assistant for our SaaS product.', messages, stream: true, }); return new Response(response.toReadableStream()); } ``` **Best for:** Customer support, Q&A, simple conversational interfaces. ## 2. RAG (Retrieval-Augmented Generation) Fetch relevant context, inject into prompt, generate grounded answer. ```typescript async function ragQuery(question: string) { // 1. Embed the question (use Voyage, OpenAI, or Cohere — not Anthropic) const embedding = await embeddingClient.embed(question); // 2. Search vector DB for relevant chunks const chunks = await vectorDb.query(embedding, { topK: 5 }); // 3. Send to Claude with context const message = await client.messages.create({ model: 'claude-sonnet-4-20250514', max_tokens: 2048, system: `Answer based on the provide...