> ## Documentation Index > Fetch the complete documentation index at: https://docs.veval.dev/llms.txt > Use this file to discover all available pages before exploring further. # Traces > A trace is a recorded agent run. A trace records one run of your agent: its input, its output, every step in between, and the timing and cost of the whole run. Every call to `RunAsync` produces one trace, whether the agent succeeds or throws. ## How traces fit in A trace is made of [steps](/concepts/steps). Your agent records a step for each LLM call or sub-operation it wraps in `TrackStepAsync`. Traces are the raw material for testing. A [scenario](/concepts/scenarios) item can replay a trace, [replay](/concepts/replay) uses a trace's recorded outputs in place of live LLM calls, and a [snapshot](/concepts/snapshots) is saved from a known-good trace. ## What a trace records | Field | Description | | - | - | | Trace ID | Unique ID for the run, prefixed `tr_`. Generated by the SDK. | | Agent name | The name you pass to `RunAsync`. Identifies the agent in the dashboard. | | Input | The optional input you pass to `RunAsync`. | | Output | The value your agent returned. | | Status | `success`, or `error` if your agent threw. | | Error | The exception message when the status is `error`. | | Timing | Start time, end time, and total duration. | | Total cost | The sum of `cost_usd` across all steps. | | Metadata | Key/value pairs you attach with `SetMetadata`. | | Steps | Every step recorded during the run, in order. | ## Status | Status | Meaning | | - | - | | `success` | Your agent returned normally. | | `error` | Your agent threw. The SDK records the error message, ships the trace, and rethrows. | ## Ingestion The SDK sends the trace when the run finishes. Traces are ingested asynchronously, so a trace can take a moment to appear in the dashboard or be returned by `GetTraceAsync`. ## Deep dives What a step records and how steps are matched. Record traces, steps, and metadata.