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+# Structured logging
+
+StableRoute backend uses request-scoped correlation via `X-Request-Id` (see
+`docs/middleware-order.md`). Each handler calls `sendError` / `recordEvent` with
+the active request id so operators can trace a single client call through audit
+events and Prometheus gauges.
+
+Recommended log fields when extending handlers:
+
+- `requestId` — propagated from middleware
+- `route` — Express path template
+- `status` — HTTP status emitted
+- `eventType` — audit log category when applicable
+
+Pair and webhook mutations emit structured audit events (`pair.registered`,
+`webhook.created`, etc.) rather than ad-hoc `console.log` output.