Instrument applications with the OpenTelemetry SDK and prove the telemetry is good by validating it against a local Kopai backend. Use when setting up observability, adding tracing/logging/metrics, deciding what to instrument or which attributes to add, retrofitting OTel into an existing codebase, threading context through call chains, configuring sampling, or when traces/logs/metrics aren't appearing after setup. Also use when users say things like "my traces aren't showing up", "I don't see any data", or "how do I add observability to my app". Do NOT use to investigate existing telemetry for a root cause (use root-cause-analysis), to build dashboards (use create-dashboard), or to instrument LLM and agent calls (use otel-genai-instrumentation).