Tracing¶
Tracing captures a chatbot's inputs, outputs, and decision-making process so bot developers can understand and debug their chatbot's behavior.
Open Chat Studio provides builtin tracing for all users. You can optionally connect an external Langfuse tracing provider to get additional span-level detail.
Builtin Tracing¶
Builtin tracing is always available — no feature flag or external service is required. A trace is recorded automatically for every conversation turn.
Each builtin trace captures:
- Input — the message sent by the participant
- Output — the response generated by the bot
- Duration — how long the turn took to complete
- Session data snapshot — a point-in-time record of the session state
- Participant data snapshot — a point-in-time record of the participant's data
Note
Builtin tracing records top-level information only. It does not include span-level detail (individual LLM calls, tool calls, retrieval steps, etc.). To see spans, configure a Langfuse provider.
Langfuse External Tracing¶
Langfuse is an optional external tracing provider. When Langfuse is configured for a bot, OCS sends detailed trace data to Langfuse and enriches the trace detail page with span-level information.
Tracing begins automatically with the next conversation after you configure a Langfuse provider.
Trace Detail Page¶
When Langfuse is configured, the trace detail page in Open Chat Studio includes:
- A span tree panel that lets you inspect exactly what happened inside a single trace.
- A direct link to the corresponding trace in the Langfuse UI.
The span tree panel is split into two panes:
- Left pane — the full Langfuse observation tree, with colored status dots and latency badges for each span.
- Right pane — the input and output for the selected span, shown as readable text by default, with a "Show raw JSON" toggle for the underlying Langfuse data.
When the panel loads, it automatically selects the first span that has an error status, or the first span overall if no errors are present. This makes it easy to jump straight to the root cause of a problem.
Note
The span tree panel only appears when a Langfuse tracing provider is configured for your bot. If no Langfuse provider is configured, no trace information exists for the session, or the Langfuse API returns an error, the panel is hidden and the rest of the page is unaffected.