The OpenTelemetry SDK is a JavaScript or Node.js implementation for generating, processing, and exporting telemetry. It supports manual instrumentation when automatic agents cannot expose business-logic signals. section 4.3.1 section 4.6
Use the SDK when:
- Auto-instrumentation provides a useful baseline but treats the service as a black box. section 4.3.1
- Application code must be modified to emit signals that represent business logic. section 4.3.1
- Telemetry needs vendor-neutral metadata and correlation through semantic conventions. section 4.6
JavaScript application instrumentation
An automatically instrumented JavaScript application can provide baseline telemetry; adding the OpenTelemetry SDK lets developers manually emit signals for business logic that automatic instrumentation cannot see. section 4.3.1
