Tracing is one of the three pillars of observability. Tracing an API call in WSO2 API Manager is important to observe, identify possible bottlenecks in an API invocation path, and debug them. WSO2 API Manager facilitates tracing API invocation paths and publishing the traces based on the OpenTelemetry standard, using multiple tracers, namely: OpenTelemetry Protocol (OTLP), Jaeger, Zipkin, Log & Custom Tracer. This demo outlines important concepts of OpenTelemetry based distributed tracing in WSO2 API Manager, followed by a demonstration of publishing traces using the OTLP Tracer to Elastic APM, when invoking a sample API.