iii-observability

The iii-observability worker provides OpenTelemetry-backed observability for the iii engine: distributed tracing, structured logs, metrics with rollups, alert rules, sampling configuration, and baggage propagation. Every surface is a callable engine::* function, plus a single log reactive trigger that fires on every ingested log entry. Functions span nine sub-namespaces, emit, query stored telemetry, inspect configuration, and propagate context.

The worker is on by default (enabled: true). When disabled, the emit and read functions still register but become no-ops and the trigger never fires. Core config: service_name/service_version/service_namespace (OTel resource attributes), exporter (memory | otlp | both), endpoint (OTLP collector URL, default http://localhost:4317), sampling_ratio (0.0, 1.0), memory_max_spans, and per-pillar toggles/limits (metrics_enabled, logs_enabled, retention and count caps). Most fields accept OTEL_* env overrides. The in-memory query functions (logs, traces) require the memory or both exporter.

Traces and metrics use OTLP/gRPC by default; https:// endpoints enable TLS and http:// endpoints use cleartext. Set OTEL_EXPORTER_OTLP_PROTOCOL=http/protobuf to use OTLP/HTTP protobuf for traces and metrics, or use OTEL_EXPORTER_OTLP_TRACES_PROTOCOL / OTEL_EXPORTER_OTLP_METRICS_PROTOCOL for signal-specific overrides. The HTTP/protobuf path is appended automatically (/v1/traces, /v1/metrics) when the configured endpoint is a base collector URL. Logs export over OTLP/HTTP to /v1/logs.