A user reports a hallucinated answer in prod. To fix it you need the full trace of that one request, and how fast you can pull it depends entirely on the tracing you set up months earlier.
The ticket
A support user pasted a screenshot: our agent told them a refund window was 90 days. The real policy is 30. Wrong answer, confidently stated, already sent. The ticket had a request id in the response headers and nothing else.
The only useful question at that point is: what actually happened inside that one request. Which chunks did retrieval pull? What was the exact prompt the model saw after templating? What did each tool call return? A wrong answer is almost never the model being creative. It is usually a bad chunk, a stale document, a tool that returned the wrong row, or a prompt that got assembled wrong. You cannot see any of that from the output. You have to open the trace for that specific request id and read the spans.
The axis that matters
