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Signed-off-by: Antonio Ereiz <antonio.ereiz@gmail.com>

docs/tutorials/setup-opentelemetry.md

@@ -33,6 +33,7 @@ const {
 } = require('@opentelemetry/auto-instrumentations-node');
 const { PrometheusExporter } = require('@opentelemetry/exporter-prometheus');
 
+// By default exports the metrics on port 9464
 const prometheus = new PrometheusExporter();
 const sdk = new NodeSDK({
   // You can add a traceExporter field here too