# Testing

In the [inbox](/docs/inbox/), hover over a message and click the **⋯** button, then select **View workflow run** to open the workflow viewer. Right-clicking the message opens the same menu.

## The workflow graph

The viewer shows your workflow as a visual graph. Steps that ran are highlighted, and the edges between them show the exact path the message took. Steps that were not reached stay dimmed. If a step errored, it's marked in red.

## Step details

Click any step in the graph to open a detail panel with its outcome (ok, error, pause, or skipped), duration in milliseconds, input args, and output. If the step failed, you'll see the error message. Args that didn't change from the previous step are collapsed.

Branch steps show which case matched. Prompt steps include the model used.

## Sub-workflows

When a step routes to a sub-workflow via a [workflow action](/docs/ai/workflows/actions/), click **Open workflow** in the detail panel to see that sub-workflow's graph and trace.