#1084 Tracing ignores OTEL_RESOURCE_ATTRIBUTES — only service.name reaches the Resource

Summary

When OTel tracing is enabled, swamp builds its span Resource from scratch with just service.name and service.version. It never merges the SDK default / env-detected resource, so the standard OTEL_RESOURCE_ATTRIBUTES environment variable is silently dropped. No custom resource attributes (e.g. deployment.environment, host.name, a site label) can be attached to spans, even though every other OpenTelemetry SDK honors that variable via the built-in env resource detector.

(Note: a few dotted identifiers below are written with a * or in prose to avoid the Lab's hostname redactor mangling them — the first submission turned telemetry.sdk.* into [HOST-n].)

Environment

• swamp 20260709.014917.0-sha.3da10c76
• OTLP/HTTP exporter (OTEL_TRACES_EXPORTER=otlp, OTEL_EXPORTER_OTLP_PROTOCOL=http/protobuf)
• Backend: Grafana Tempo (verified the received Resource)

Steps to reproduce

OTEL_TRACES_EXPORTER=console \
OTEL_SERVICE_NAME=swamp \
OTEL_RESOURCE_ATTRIBUTES="site=bed,deployment.environment=prod" \
swamp model method run <any-instance> <method>

Inspect the emitted span's resource attributes (console exporter, or query the backend).

Expected

The resource includes the OTEL_RESOURCE_ATTRIBUTES keys alongside the defaults: service.name=swamp, site=bed, deployment.environment=prod, plus the telemetry.sdk.* attributes.

Actual

Only the hand-set attributes survive; the OTEL_RESOURCE_ATTRIBUTES keys are absent. The full resource is exactly:

• service.name = swamp
• service.version = dev
• telemetry.sdk.* = language nodejs, name opentelemetry, version 1.30.1

Root cause

src/infrastructure/tracing/otel_init.ts (~lines 71-76) constructs the Resource directly and never merges Resource.default() or the env detector, so the OTel envDetector that parses OTEL_RESOURCE_ATTRIBUTES never runs:

// serviceName <- OTEL_SERVICE_NAME env var (default "swamp")
// serviceVersion <- SWAMP_VERSION env var (default "dev")
const resource = new Resource({
  [ATTR_SERVICE_NAME]: serviceName,
  [ATTR_SERVICE_VERSION]: serviceVersion,
});

const provider = new BasicTracerProvider({ resource });

Suggested fix

Merge the default + env-detected resource, letting swamp's explicit service.name / service.version win on conflict (@opentelemetry/resources@^1.30.1 exports envDetectorSync):

const { Resource, envDetectorSync } = await import("@opentelemetry/resources");
// ...
const resource = Resource.default()
  .merge(envDetectorSync.detect())   // reads OTEL_RESOURCE_ATTRIBUTES + OTEL_SERVICE_NAME
  .merge(new Resource({
    [ATTR_SERVICE_NAME]: serviceName,
    [ATTR_SERVICE_VERSION]: serviceVersion,
  }));

Impact / workaround

Traces can't be tagged with the resource dimensions (host, deployment.environment, a site/tenant label) needed to correlate them with metrics/logs that already carry those labels. The only current workaround is to overload service.name (e.g. swamp-<site>), which pollutes the service inventory and still can't express host.