中文 | English
A practical roadmap for AI application engineers: from LLM basics, Prompt Engineering, RAG, Agent, MCP, evaluation, to production deployment.
A hands-on learning repository for developers who want to build reliable LLM applications, not just demos.
This repository brings together learning paths, core concepts, practical tutorials, checklists, templates, bad cases, production notes, and interview preparation. The goal is to help you grow from "I can call a model API" to "I can design, evaluate, deploy, and improve an AI application."
AI application engineer = someone who connects model capabilities to real product and business workflows, while keeping the system stable, observable, controllable, evaluable, and production-ready.
- Online website: Website
- Online docs index: All Pages
- Bilingual tutorial: Build a Personal Knowledge Base Assistant
- Chinese tutorial: 从 0 到 1 构建个人知识库问答助手
- RAG production checklist: RAG Production Checklist
- Agent safety checklist: Agent Safety Checklist
- Prompt review checklist: Prompt Review Checklist
- RAG bad cases: RAG Bad Cases
- Projects: Projects
- Examples: Examples
- You are new to LLM app development and do not know where to start.
- You understand prompting, but do not know how to build RAG, Agents, or tool calling.
- You can build demos, but do not know how to evaluate, deploy, monitor, and control cost.
- You want to move toward AI application engineering, but need portfolio projects.
- You can explain concepts, but cannot yet describe an end-to-end production system.
flowchart LR
A["Start Here<br/>Learning Map"] --> A1["Foundations<br/>API, JSON, Data Flow"]
A1 --> B["LLM Basics<br/>Token, Context, Hallucination"]
B --> C["Prompt Engineering<br/>Structured Instructions"]
C --> D["RAG<br/>Knowledge Base Q&A"]
D --> E["Agent<br/>Tool Calling and Workflows"]
E --> F["MCP<br/>Connect Tools and Data Sources"]
F --> G["Evaluation<br/>Eval Sets and Regression"]
G --> H["Production<br/>Deploy, Monitor, Control Cost"]
H --> I["Projects<br/>Portfolio and Interview"]
| Stage | Goal | Recommended Content | Output |
|---|---|---|---|
| 0. Preparation | Build the learning map and engineering foundation | Start Here, Foundations | Minimal chat demo and data-flow diagram |
| 1. LLM Basics | Understand model behavior, context, tokens, hallucination, and cost | LLM Basics | Explain what happens in one model API call |
| 2. Prompt Engineering | Design stable, reusable, testable prompts | Prompt Engineering | Reusable prompt template |
| 3. RAG | Build document Q&A and knowledge-base systems | RAG | Personal knowledge base assistant |
| 4. Agent | Let models call tools and execute workflows | Agent | Weekly report assistant or coding assistant |
| 5. MCP | Connect tools, data sources, and AI clients through a shared protocol | MCP | Minimal local MCP server |
| 6. Evaluation | Evaluate quality, stability, safety, latency, and cost | Evaluation | Eval dataset and scoring script |
| 7. Production | Deploy with logging, permissions, monitoring, fallback, and cost control | Production | Production-ready AI app |
| 8. AI Coding | Use AI coding tools effectively | AI Coding | Personal AI coding workflow |
| 9. Interview | Prepare AI application engineering interviews | Interview | Clear project story |
| Type | Resource | Useful For |
|---|---|---|
| End-to-end tutorial | Personal Knowledge Base Assistant | Build your first RAG project |
| Web tutorial | English Web Tutorial | Read online |
| Launch checklist | RAG Production Checklist | Moving a RAG demo toward production |
| Safety checklist | Agent Safety Checklist | Designing safer tool calling and Agents |
| Prompt checklist | Prompt Review Checklist | Making prompts more stable and testable |
| Failure cases | RAG Bad Cases | Understanding common RAG failures |
| Architecture template | AI App Architecture Template | Writing project README, design docs, and interview notes |
| Eval template | Eval Dataset Template | Creating AI app evaluation datasets |
| Example | Covers | Entry |
|---|---|---|
| Minimal RAG | Chunking, retrieval, context-grounded answers | examples/minimal-rag |
| Tool Calling | Tool schema, function call, result injection | examples/tool-calling |
| Minimal MCP Server | MCP tool definition and local file search | examples/minimal-mcp-server |
Start Here
-> AI Application Foundations
-> LLM Basics
-> Prompt Engineering
-> RAG
-> Agent
-> MCP
-> Evaluation
-> Production
-> Tutorials / Checklists / Bad Cases
-> Projects
- Developers learning LLM application development systematically.
- Backend or full-stack engineers moving into AI application engineering.
- Builders working on RAG, Agents, AI assistants, knowledge bases, or automation workflows.
- Candidates preparing for AI application engineer, Agent engineer, or LLM engineer interviews.
- Product, operations, and data people who want to understand the AI app delivery lifecycle.
- People who only want to study model training or low-level ML algorithms.
- People who only collect links and do not build projects.
- People expecting to master all AI engineering topics in a few days.
High-quality tutorials, project cases, bad cases, templates, and engineering lessons are welcome. Please read CONTRIBUTING.md first.
If this repository helps you, feel free to star it so more developers can find a practical path into AI application engineering.