Architecture Observability

8.10. Observability Flow

Prometheus, Grafana, Langfuse, OpenTelemetry Collector, Tempo, Loki, and service instrumentation boundaries.

1. Diagram

Open the full-size diagram.

2. Notes

Langfuse is deliberately outside the OTel path. LiteLLM sends Langfuse traces through its own success_callback/failure_callback, not through the Collector. Langfuse is the LLM-behavior layer; Prometheus and Grafana are the infrastructure-metrics layer. Backend, Celery workers, and LiteLLM OTLP traces reach Tempo through the Collector. OTLP logs use the same receiver. The Collector redacts a documented field allowlist and persists accepted logs in Loki with trace and span metadata.

3. Source Files

• services/backend/service.yml
• services/celery/service.yml
• services/litellm/service.yml
• services/prometheus/service.yml
• services/grafana/service.yml
• services/loki/service.yml
• services/tempo/service.yml
• services/otel-collector/service.yml