Traces, sessions, and logs
Find a request, inspect its spans, follow a conversation, and read related logs.
A trace is one request through your application. Each step inside it, such as a model call, a tool call, or an agent step, is a span. Use the trace explorer to find failed or slow requests and to see what each model call received and returned.
Find a trace or span
Select Traces in the project sidebar. Use the Traces and Spans switch above the table to list whole requests or single operations.
Both lists have the same filters:
| Filter | What it does |
|---|---|
| Search | Matches trace names or span names. It does not search prompt or response content. |
| Status | Shows All statuses, success, or error. |
| Environment | Lists up to 100 environment names from your telemetry. |
| Framework | Lists the frameworks detected in your telemetry. |
| Conversation | Select a value in the Session or Conversation column. A chip shows the filter; select it to clear the filter. |
| User | Select a value in the User column. A chip shows the filter; select it to clear the filter. |
The filters are part of the page URL, so you can bookmark or share a filtered view.
The lists cover the project’s whole retention period. They have no date-range control. Scroll to the end of the table or select Load More to load the next page.
Trace columns
The trace list shows Date and Trace, plus these columns: Input, Output, Duration, Tokens, Cost, Spans, Models, Session, User, and Environment.
- Input and Output show the start of the request’s prompt and reply.
- Duration shows the time to first token when you hover over it, if the trace has that value.
- Tokens shows input and output tokens. Hover over it for cache-read and reasoning tokens.
- Spans shows the span count and the number of spans with errors.
Span columns
The span list shows Date, Type, and Name, plus these columns: Model, Tool / Agent, Conversation, Service, Environment, Status, Duration, Tokens, and Cost.
Select a span row to open its trace with that span selected.
Choose columns
Select Columns to show or hide columns. Environment is hidden by default in both lists, and Service is hidden by default in the span list. Your browser keeps the choice for later visits.
Inspect a trace
Select a trace row to open the trace. The header shows Status, Duration, First token, Spans, Tokens, Cost, Started, Service, Environment, Framework, User, Conversation, and Trace ID. Some fields appear only when the trace has a value for them.
The span waterfall shows each span on a shared time axis, nested under its parent. Drag the column edges to resize the span and operation columns. Select Expand all or Collapse all to open or close the tree.
Move through spans with the keyboard
Focus the span tree, then use these keys:
| Key | Action |
|---|---|
↓ or j |
Select the next span |
↑ or k |
Select the previous span |
PageDown or PageUp |
Move eight spans down or up |
Home or End |
Select the first or last span |
→ or l |
Expand a span, or select its first child |
← or h |
Collapse a span, or select its parent |
Read a span
The span panel shows fields such as Model, Provider, Agent, Tool, Duration, First token, Tokens, Cost, Finish, Operation, Conversation, Response ID, and Span ID, plus the span’s Metadata.
Below the fields, tabs show the span’s data when it has any:
- Input / Output: the prompt and the reply. Select Pretty for formatted chat messages or JSON for the stored value.
- Attributes: the span attributes.
- Events: the span events and their attributes.
- Error: the error message and details.
A Truncated badge means that the dashboard shows a preview of a long value, not the full value. A Truncated at source badge next to the span name means that the sender cut the content before export, so telemetry.dev never received the rest.
If prompt and response capture is off for the environment, the Input / Output tab does not appear and the span name is [REDACTED]. Read What capture-off removes.
Follow a conversation
Select Sessions in the project sidebar to list conversations. A session groups the traces that share a session ID. To set one, read Add user, session, and metadata for TypeScript or Python.
Select 24h, 3d, 7d, or 30d to set the time range. You can search by session ID or trace name and filter by agent, user, or model. The list shows each session’s Agent, Model, Customer, Turns, Tokens, Cost, and Last active time.
Select a session to see a timeline of its model calls, tool calls, errors, and idle time, followed by each turn of the conversation. Select Open in Traces to list the session’s traces, or Open trace if the session has one trace.
Read logs
Select Logs in the project sidebar. The table shows Date, Level, Entity, Message, and Data.
The level filter starts at error. You can also select warn, info, debug, or All levels.
The table loads the newest 100 matching log records from the last 30 days, or from the retention period if that is shorter. It has no further pages. The search box filters only the message previews in those loaded records.
Select a row to open the log details, with the full message, level, service, environment, the related trace, and the log’s data. If the log has trace context, select Trace to open the trace with the log’s span selected.