What problem does it solve? Production features often ship without telemetry, so when something breaks, engineers cannot tell what happened from the available data. This Skill guides you to instrument code alongside the feature so production behavior is visible and diagnosable from day one. ## Core Features & Use Cases - Structured Logging: Enforces JSON log events with stable event names, consistent log levels, mandatory correlation/request IDs, and strict rules against logging secrets or PII. - Metrics and Tracing: Applies RED (Rate, Errors, Duration) and USE (Utilization, Saturation, Errors) methods with bounded label cardinality, histogram-based latency percentiles, and OpenTelemetry distributed tracing. - Symptom-Based Alerting: Designs actionable alerts tied to user-facing symptoms with runbook links, justified thresholds, and two-severity paging, plus a verification pass that test-fires alerts and validates telemetry output. - Use Case: When adding a payment retry flow with an external provider, use this Skill to define the on-call questions first, then emit structured failure events, RED metrics on the provider calls, and an alert on elevated error rates. ## Quick Start Instrument my new checkout endpoint with structured logs, RED metrics, and an OpenTelemetry trace, then define the alerts an on-call engineer would need.
