What dependency telemetry would you want from a backend API?

Capture dependency telemetry for SQL, Redis, and HTTP calls

Explains dependency duration, error rate, timeout rate, query tagging, Redis latency, HTTP downstream calls, and endpoint correlation.

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TL;DR

I would capture dependency name, operation, duration, success or failure, timeout status, retry count, and correlation id. For SQL, I want query duration, query count per request, query tags for important endpoints, and enough plan or query identity to investigate safely. For Redis, I want command latency, timeout count, hit/miss where the app can provide it, and key pattern rather than raw keys with sensitive data.

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SQL, Redis, HTTP dependencies, duration, error rate, timeouts, retries, query tags, cache misses, and endpoint correlation.

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Why this question matters
Many API incidents are dependency incidents wearing an API mask. Good dependency telemetry separates app code from SQL, Redis, queues, and downstream HTTP calls.
I would capture dependency name, operation, duration, success or failure, timeout status, retry count, and correlation id. For SQL, I want query duration, query count per request, query tags for important endpoints, and enough plan or query identity to investigate safely. For Redis, I want command latency, timeout count, hit/miss where the app can provide it, and key pattern rather than raw keys with sensitive data.
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For downstream HTTP calls, I would track service name, normalized route or operation, status category, duration, timeout, circuit-breaker behavior, and retry attempts. This lets me separate local CPU or queueing from SQL, Redis, and provider latency, and it exposes a retry storm that makes one incident look like several unrelated API failures. I would connect dependency spans and metrics to the affected endpoint and user journey, preserve the trace relationship across asynchronous work, and compare dependency time with the request's full latency budget rather than reading each chart in isolation.

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Details

Only measuring total request duration.
Using raw user values as metric labels.
Not distinguishing timeout from other dependency failures.
No way to connect slow SQL or Redis calls to a specific endpoint.

What dependency telemetry would you want from a backend API?

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