diff --git a/backend/.env.example b/backend/.env.example
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+++ b/backend/.env.example
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+# Database
+DATABASE_URL=postgresql://postgres:postgres123@localhost:5432/ai_clinical_research?schema=public
+
+# Redis
+REDIS_URL=redis://localhost:6379
+
+# JWT
+JWT_SECRET=your-secret-key-change-in-production
+JWT_EXPIRES_IN=7d
+
+# LLM API
+DEEPSEEK_API_KEY=your-deepseek-api-key
+DASHSCOPE_API_KEY=your-qwen-api-key
+
+# Dify
+DIFY_API_URL=http://localhost:3000
+DIFY_API_KEY=your-dify-api-key
+
+# Server
+PORT=3001
+NODE_ENV=development
diff --git a/frontend/.env.example b/frontend/.env.example
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--- /dev/null
+++ b/frontend/.env.example
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+# API
+VITE_API_URL=http://localhost:3001
+VITE_API_TIMEOUT=30000
+
+# Environment
+VITE_NODE_ENV=development