Orphaned spans (no root spans) often occur when parent spans are missing or not ingested, which can happen if spans are sent out of order, dropped, or if context propagation is misconfigured across services. In Phoenix, a root span is defined as any span whose parent is not present in the collection; this can be temporary if the parent arrives later. This issue is more common in distributed or multi-service environments, especially if trace context (trace ID, parent span ID) is not properly propagated between services or containers, or if network or exporter configuration differs from your local setup.
To troubleshoot, check that your Mastra app and all services are correctly propagating trace context (e.g., via HTTP headers), and that all spans are being exported to Phoenix without being dropped. Also, ensure that the Phoenix collector endpoint is reachable and consistent across your staging environment. For more details on root span handling and context propagation, see the <https://arize.com/docs/phoenix/tracing/how-to-tracing/setup-tracing/custom-spans#芦R3l38ut1letrnb禄|Phoenix custom spans guide> and <https://arize.com/docs/phoenix/integrations/mastra/mastra-tracing|Mastra tracing integration>.
Would you like more detail on debugging context propagation or exporter setup?
Sources:
- <https://arize.com/docs/phoenix/tracing/how-to-tracing/setup-tracing/custom-spans#芦R3l38ut1letrnb禄|Phoenix custom spans guide>
- <https://arize.com/docs/phoenix/integrations/mastra/mastra-tracing|Mastra tracing integration>
