# Correlation Tracing

> Implement distributed tracing with correlation IDs, trace propagation, and span tracking across m…

Implement distributed tracing with correlation IDs, trace propagation, and span tracking across microservices. Use when debugging distributed systems, monitoring request flows, or implementing observability.

- Page: https://ss33.ai/skills/aj-geddes/correlation-tracing-89653454837
- Publisher: aj-geddes
- Category: [Software Development](https://ss33.ai/skills/category/software-development-t44z8z) › [DevOps & cloud](https://ss33.ai/skills/category/software-development-t44z8z/devops-and-cloud-unkt50)
- License: MIT
- Source: https://github.com/aj-geddes/useful-ai-prompts/blob/3f5182cfd739fc113f4af5244a1cf342ad7f7911/skills/correlation-tracing/SKILL.md

## Skill

SKILL.md: https://ss33.ai/api/v1/ss33/download/aj-geddes/correlation-tracing-89653454837

# Correlation & Distributed Tracing

## Table of Contents

- [Overview](#overview)
- [When to Use](#when-to-use)
- [Quick Start](#quick-start)
- [Reference Guides](#reference-guides)
- [Best Practices](#best-practices)

## Overview

Implement correlation IDs and distributed tracing to track requests across multiple services and understand system behavior.

## When to Use

- Microservices architectures
- Debugging distributed systems
- Performance monitoring
- Request flow visualization
- Error tracking across services
- Dependency analysis
- Latency optimization

## Quick Start

Minimal working example:

```typescript
import express from "express";
import { v4 as uuidv4 } from "uuid";

// Async local storage for context
import { AsyncLocalStorage } from "async_hooks";

const traceContext = new AsyncLocalStorage<Map<string, any>>();

interface TraceContext {
  traceId: string;
  spanId: string;
  parentSpanId?: string;
  serviceName: string;
}

function correlationMiddleware(serviceName: string) {
  return (
    req: express.Request,
    res: express.Response,
    next: express.NextFunction,
  ) => {
    // Extract or generate trace ID
    const traceId = (req.headers["x-trace-id"] as string) || uuidv4();
    const parentSpanId = req.headers["x-span-id"] as string;
    const spanId = uuidv4();
// ... (see reference guides for full implementation)
```

## Reference Guides

Detailed implementations in the `references/` directory:

| Guide | Contents |
|---|---|
| [Correlation ID Middleware (Express)](references/correlation-id-middleware-express.md) | Correlation ID Middleware (Express) |
| [OpenTelemetry Integration](references/opentelemetry-integration.md) | OpenTelemetry Integration |
| [Python Distributed Tracing](references/python-distributed-tracing.md) | Python Distributed Tracing |
| [Manual Trace Propagation](references/manual-trace-propagation.md) | Manual Trace Propagation |

## Best Practices

### ✅ DO

- Generate trace IDs at entry points
- Propagate trace context across services
- Include correlation IDs in logs
- Use structured logging
- Set appropriate span attributes
- Sample traces in high-traffic systems
- Monitor trace collection overhead
- Implement context propagation

### ❌ DON'T

- Skip trace propagation
- Log without correlation context
- Create too many spans
- Store sensitive data in spans
- Block on trace reporting
- Forget error tracking