Explain API Observability with Tracing.

Example

When you log into an app, the request flows through authentication, database, and notification services. Tracing shows which step slowed down or failed.

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Why Is It Important

Without tracing, errors are “black boxes.” With it, you gain end-to-end visibility into requests, making debugging faster and improving user experience.

Interview Tips

In interviews, explain how tracing complements logs and metrics. Mention real-world use cases (like login flows) and highlight the role of trace IDs in following a request across services.

Trade-offs

Tracing provides deep insights but requires instrumentation effort, can slightly impact performance, and generates lots of data. Teams often mitigate this with sampling strategies.

Pitfalls

Common mistakes include failing to propagate trace IDs or tracing everything (causing data overload). Focus on critical paths to balance value and cost.