---
title: Introduction
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Once you’ve created a workflow, it’s important to test it thoroughly before going live. Dify offers a full set of debugging tools that let you troubleshoot issues, track variable flow, and review detailed execution logs — all in one place.

Dify provides a comprehensive debugging toolset to help you quickly locate issues, inspect variable transmission, and view detailed logs.

This article introduces the full workflow debugging process, including single-node debugging, variable inspection, execution history, and end-to-end testing.

![](https://assets-docs.dify.ai/2025/06/8e7933b45a69241a9861a09fa47d5c62.png)

## Debugging a Workflow Application

### Single Node Debugging

If a specific node causes the workflow to fail, you can debug that node individually to quickly identify the issue.

To test a single node, click the debug icon in its top-right corner. Try entering some simple test data and observe the output. You can gradually introduce more complex input to see how the node responds.

For more details, see [Debug Node](/en/guides/workflow/debug-and-preview/debug-node).

![](https://assets-docs.dify.ai/2025/06/44decb6644b140e46ed2e1e9246f48f7.png)

### Step-by-Step Node Debugging

This method lets you trace how data flows through each step — from one node to the next — helping you catch issues in real-time.

For detailed usage, see [Variable Inspection](/en/guides/workflow/debug-and-preview/variable-inspect).

![](https://assets-docs.dify.ai/2025/06/887630764b180a60becb6a4fcee2c622.png)

### View Node Execution History

Click “Last Run” in the node panel to review logs from the most recent execution — including inputs, outputs, timing, and any errors.

See [Debug History - Node Logs](/en/guides/workflow/debug-and-preview/history-and-logs#node-execution-logs) for more details.

![](https://assets-docs.dify.ai/2025/06/a6011d5966c78a4d1705f2af44ed8af1.png)

### Debugging the Entire Workflow

After you’ve confirmed that each individual node works as expected, it’s time to test the entire workflow from start to finish.

Use the Preview feature to experience the final user interface. This mode displays the input fields, output area, and interaction flow — ideal for confirming user experience expectations. During preview, the system performs an auto-check to ensure all nodes are configured correctly and connected.

![](https://assets-docs.dify.ai/2025/06/de00849b363ec9356e5764b88b4331fb.png)

#### Configuration Checklist

Before you run the full workflow, Dify will automatically check for missing parameters, misconfigurations, or disconnected nodes — and prompt you to fix them.

![](https://assets-docs.dify.ai/2025/06/85bafda1f786549c22404cd5ec711d0f.png)

While running the workflow, you can view each node's execution status on the right panel, including input/output and logs. Use the status indicators (green = success) to identify where a failure may have occurred.

It’s recommended to perform multiple test rounds with varying data types and complexities to verify workflow stability before going live.

![](https://assets-docs.dify.ai/2025/06/c09f788f77b5f8ebdd635ddba66a1b99.png)

## View Application Logs

After publishing your application, you can monitor how it’s performing and how users interact with it. Dify’s logs and monitoring tools help you troubleshoot issues, track performance trends, and better understand user behavior.

![](https://assets-docs.dify.ai/2025/06/6dd8e8a7186089a390679b6de4bb97b9.png)

For more information, see:

- [Run History](/en/guides/workflow/debug-and-preview/history)
- [Monitoring](/en/guides/monitoring/README)

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