# 🚀 Advanced AI Development Guide

## 📋 Table of Contents
- [Getting Started](#getting-started)
- [Architecture Overview](#architecture)
- [Implementation Details](#implementation)
- [Best Practices](#best-practices)

---

## 🎯 Getting Started

### Prerequisites
\`\`\`bash  
npm install @langfuse/core  
pip install langfuse  
\`\`\`

### Quick Setup
1. **Initialize your project**
   \`\`\`typescript  
   import { Langfuse } from 'langfuse'  

   const langfuse = new Langfuse({  
     secretKey: process.env.LANGFUSE_SECRET_KEY,  
     publicKey: process.env.LANGFUSE_PUBLIC_KEY,  
     baseUrl: 'https://cloud.langfuse.com'  
   })  
   \`\`\`

2. **Create your first trace**
   \`\`\`python  
   from langfuse import Langfuse  

   langfuse = Langfuse()  
   trace = langfuse.trace(name="chat-application")  
   \`\`\`

---

## 🏗️ Architecture Overview

### System Components

| Component | Description | Status |
|-----------|-------------|--------|
| **Core Engine** | Main processing unit | ✅ Active |
| **API Gateway** | Request routing | ✅ Active |
| **Data Store** | Persistence layer | ⚠️ Maintenance |
| **Analytics** | Metrics & insights | 🚧 Development |

### Data Flow

```mermaid
graph TD
    A[User Request] --> B[API Gateway]
    B --> C{Route Decision}
    C -->|Trace| D[Trace Handler]
    C -->|Generation| E[Generation Handler]
    C -->|Score| F[Score Handler]
    D --> G[Database]
    E --> G
    F --> G
```

---

## ⚙️ Implementation Details

### Trace Management

> **Note:** Traces are the foundation of observability in LLM applications.

#### Creating Traces
\`\`\`typescript  
// Basic trace creation  
const trace = langfuse.trace({  
  name: "user-query-processing",  
  userId: "user-123",  
  sessionId: "session-456",  
  metadata: {  
    environment: "production",  
    version: "2.1.0"  
  }  
})  

// Nested observations  
const span = trace.span({  
  name: "document-retrieval",  
  input: { query: "What is machine learning?" },  
  metadata: { vectorStore: "pinecone" }  
})  

const generation = span.generation({  
  name: "answer-generation",  
  model: "gpt-4",  
  input: retrievedDocs,  
  output: generatedAnswer,  
  usage: {  
    promptTokens: 1250,  
    completionTokens: 420,  
    totalTokens: 1670  
  }  
})  
\`\`\`

### Advanced Features

#### 🔄 Async Processing
\`\`\`python  
import asyncio  
from langfuse import Langfuse  

async def process_batch():  
    langfuse = Langfuse()  

    tasks = []  
    for item in batch_items:  
        task = asyncio.create_task(  
            process_item_with_tracing(langfuse, item)  
        )  
        tasks.append(task)  

    results = await asyncio.gather(*tasks)  
    return results  
\`\`\`

#### 🎯 Custom Scoring
\`\`\`typescript  
// Automated scoring  
trace.score({  
  name: "relevance",  
  value: 0.95,  
  comment: "Highly relevant response"  
})  

// Human feedback scoring  
trace.score({  
  name: "user-satisfaction",  
  value: 1,  
  source: "user-feedback",  
  comment: "User rated 5/5 stars"  
})  
\`\`\`

---

## 🎨 Best Practices

### 📊 Monitoring & Observability

#### Key Metrics to Track
- **Latency**: P50, P95, P99 response times
- **Token Usage**: Cost optimization
- **Error Rates**: System reliability
- **User Satisfaction**: Quality metrics

#### Dashboard Setup
\`\`\`yaml  
# monitoring-config.yml  
dashboards:  
  - name: "LLM Performance"  
    panels:  
      - type: "time-series"  
        title: "Response Latency"  
        query: "avg(response_time) by (model)"  
      - type: "stat"  
        title: "Daily Token Usage"  
        query: "sum(tokens_used)"  
      - type: "table"  
        title: "Top Errors"  
        query: "topk(10, count by (error_type))"  
\`\`\`

### 🔐 Security Considerations

> ⚠️ **Important**: Never log sensitive user data in traces

#### Data Sanitization
\`\`\`python  
def sanitize_input(data):  
    """Remove PII from trace data"""  
    sanitized = data.copy()  

    # Remove email addresses  
    sanitized = re.sub(r'\\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\\.[A-Z|a-z]{2,}\\b',  
                      '[EMAIL_REDACTED]', sanitized)  

    # Remove phone numbers  
    sanitized = re.sub(r'\\b\\d{3}-\\d{3}-\\d{4}\\b',  
                      '[PHONE_REDACTED]', sanitized)  

    return sanitized  
\`\`\`

### 🚀 Performance Optimization

#### Batch Processing
\`\`\`typescript  
// Efficient batch uploads  
const batchSize = 100  
const traces = []  

for (let i = 0; i < data.length; i += batchSize) {  
  const batch = data.slice(i, i + batchSize)  
  const processedBatch = await Promise.all(  
    batch.map(item => processWithLangfuse(item))  
  )  
  traces.push(...processedBatch)  
}  

// Flush all traces at once  
await langfuse.flushAsync()  
\`\`\`

---

## 📚 Advanced Examples

### Multi-Agent System Tracing
\`\`\`python
class MultiAgentTracer:  
    def __init__(self):  
        self.langfuse = Langfuse()  

    async def orchestrate_agents(self, task):  
        # Main orchestration trace  
        main_trace = self.langfuse.trace(  
            name="multi-agent-orchestration",  
            input={"task": task}  
        )  

        # Agent 1: Research  
        research_span = main_trace.span(name="research-agent")  
        research_result = await self.research_agent.process(task)  
        research_span.end(output=research_result)  

        # Agent 2: Analysis  
        analysis_span = main_trace.span(name="analysis-agent")  
        analysis_result = await self.analysis_agent.process(research_result)  
        analysis_span.end(output=analysis_result)  

        # Agent 3: Synthesis  
        synthesis_span = main_trace.span(name="synthesis-agent")  
        final_result = await self.synthesis_agent.process(analysis_result)  
        synthesis_span.end(output=final_result)  

        main_trace.end(output=final_result)  
        return final_result  
\`\`\`

---

## 🎉 Conclusion

With proper implementation of Langfuse tracing, you can:

- ✅ **Monitor** your LLM applications in real-time
- ✅ **Debug** issues with detailed trace information
- ✅ **Optimize** performance and costs
- ✅ **Scale** your applications with confidence

### Next Steps
1. Review the [official documentation](https://langfuse.com/docs)
2. Join our [Discord community](https://discord.gg/langfuse)
3. Check out [example projects](https://github.com/langfuse/langfuse)
