Q: What is a trace?

A trace is the complete record of all actions, messages, tool calls, and data retrievals from a single initial user query through to the final response. It includes every step across all agents, tools, and system components in a session: multiple user messages, assistant responses, retrieved documents, and intermediate tool interactions.

Note on terminology: Different observability vendors use varying definitions of traces and spans. Alex Strick van Linschoten’s analysis highlights these differences (screenshot below):

Vendor differences in trace definitions as of 2025-07-02

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