The "Logic Span": Using OpenTelemetry to Trace Hallucinations

The Signal: The 500 Error of the Mind You’re staring at a "Task Failed" status in your dashboard. You check your logs and see a clean 200 OK from the LLM provider. The network was fast, the JSON parsed correctly, but the agent still decided that the best way to "Summarize an Invoice" was to delete the database entry for it. Most developers use OpenTelemetry (OTel) to find slow database queries or network bottlenecks. But in 2026, the bottleneck isn't the network—it's the Reasoning. When an agent