otel-supabase-edge-style

name	otel-supabase-edge-style
description	Supabase Edge Function observability style: tiny provider-neutral OTel-shaped shim, OTLP export config, traces/logs/metrics, and LLM cost metrics.

OTel Supabase Edge Style

Hosted Supabase Edge Functions do not support the normal native OTel SDK lifecycle today. Use a tiny provider-neutral shim that looks like OTel and can be deleted later if native support lands.

Good reusable API names:

tracer.startActiveSpan("edge.chat", async (span) => { ... });
span.setAttributes({ "tenant.id": tenantId });
span.setStatus({ code: SpanStatusCode.ERROR });
meter.createCounter("llm.tokens.input").add(tokens, attrs);
histogram.record(durationMs, attrs);

Bad reusable API names:

sendSuperlogSpan(...);
recordCounter(...);
trackSuperlogEvent(...);

Keep the endpoint and headers in one setup area:

OTEL_EXPORTER_OTLP_ENDPOINT=https://intake.superlog.sh
OTEL_EXPORTER_OTLP_HEADERS=authorization=Bearer <key>

Signals

• Traces: span around the function operation and each critical provider call.
• Logs: concise structured OTLP log records for critical outcomes.
• Metrics: tenant-tagged counters/histograms for critical operations.
• LLM calls: capture llm.tokens.input / llm.tokens.output only when provider instrumentation is unavailable; tag explicit token counters with tenant, provider, model, use case, call site, and outcome. Do not calculate LLM cost in edge function code; Superlog estimates it centrally from provider/model/token data.

Use EdgeRuntime.waitUntil(...) or the runtime's equivalent when available so OTLP fetches can finish after the response is returned.