As noted in the https://cljdoc.org/d/com.github.steffan-westcott/clj-otel-sdk/0.1.5/api/steffan-westcott.clj-otel.sdk.otel-sdk#init-otel-sdk!, init-otel-sdk! may be evaluated once only. This is due to a limitation of the underlying opentelemetry-java implementation, which permits the https://www.javadoc.io/static/io.opentelemetry/opentelemetry-api/1.13.0/io/opentelemetry/api/GlobalOpenTelemetry.html#set(io.opentelemetry.api.OpenTelemetry)`OpenTelemetry`https://www.javadoc.io/static/io.opentelemetry/opentelemetry-api/1.13.0/io/opentelemetry/api/GlobalOpenTelemetry.html#set(io.opentelemetry.api.OpenTelemetry).

Thanks! I assumed that once-evaluated means it needs to be closed..

Unless you are using programmatic configuration of the SDK, the only clj-otel module you should be using in your application is clj-otel-api. There is no need to also use clj-otel-sdk. If you are just getting started using OpenTelemetry, I strongly recommend https://cljdoc.org/d/com.github.steffan-westcott/clj-otel-api/0.1.5/doc/guides#_run_with_the_opentelemetry_auto_instrumentation_agent, as this is by far the easiest of the https://cljdoc.org/d/com.github.steffan-westcott/clj-otel-api/0.1.5/doc/guides#_configure_and_run_an_application_with_telemetry. See the https://github.com/steffan-westcott/clj-otel/tree/0.1.5#quickstart for an overview on what to do.

Yep, I did the tutorials, programmatic seems better for us as I didn't find use in much of the attributes that the agent adds, and it complicates deployment with the extra jar