review-otel-patterns
Review TypeScript/JavaScript code for OpenTelemetry instrumentation patterns and guide adoption of autotel. Covers Next.js, Nuxt, Nitro, TanStack Start, SvelteKit, NestJS, Express, Hono, Fastify, Elysia, Cloudflare Workers, AWS Lambda, edge runtimes, and standalone Node. Detects unstructured tracing, missing span attributes, manual exporter setup, broken context propagation, exposed PII, and ad-hoc error handling. Covers spans, metrics, logs, structured errors, the autotel processor pipeline (tail-sampling, attribute redaction, span-name normalisation, filtering, baggage), built-in enrichers (user agent, geo, request size) and custom `defineEnricher`, `defineWorkerFetch` for Cloudflare async drains, multi-vendor OTLP backends (Honeycomb, Datadog, Grafana Cloud, Sentry, Axiom, HyperDX), `composeSpanProcessors` / `composeSubscribers` / `composePostProcessors` for pipelines, AI SDK observability with gen-ai semantic conventions, and end-to-end OTLP testing.