---
title: Flow debugger
description: Debug flows and subflows from a dedicated Workflow Studio tab. Set breakpoints and step through a paused flow to review configuration and runtime values.
locale: en-US
canonical_url: https://www.servicenow.com/docs/r/build-workflows/workflow-studio/flow-debugger.html
release: brazil
product: Workflow Studio
classification: workflow-studio
topic_type: concept
last_updated: "2026-09-10"
reading_time_minutes: 3
keywords: [flow debugger, modify inputs, flow troubleshooting]
breadcrumb: [Explore flows, Flows, subflows, and actions, Workflow Studio, Build workflows]
---

# Flow debugger

Debug flows and subflows from a dedicated Workflow Studio tab. Set breakpoints and step through a paused flow to review configuration and runtime values.

The flow debugger enables you to perform these actions.

-   Debug a flow or subflow from a dedicated Workflow Studio tab
-   Set and remove breakpoints.
-   Pause a flow or subflow at a breakpoint.
-   Review the configuration and runtime values of each step of a flow or subflow.
-   Modify the configuration of step input values.
-   View the execution details generated by modified input values.
-   Step through a flow or subflow line-by-line.
-   Step into and out of subflows.
-   Step over the next breakpoint.
-   Skip over all remaining breakpoints.
-   Resume running a paused flow or subflow.

## Access Debug mode

To debug a flow, open the flow from the Workflow Studio home page and select **Test** > **Debug**.

\[Omitted image "flow-debugger-entry.png"\] Alt text: Entry point for the debug mode.

## Debug interface and components

A Workflow Studio debug mode tab displays flow execution details in a debugging view.

\[Omitted image "example-flow-debugger-flow.png"\] Alt text: Controls available on a debug mode tab.

A Workflow Studio debugging view tab consists of these elements.

-   **1. Debug mode label**

    Indicates that you're debugging the current flow or subflow.

-   **2. Debug controls**

    Select a debug control to step through a flow or subflow line-by-line.

    -   Resume a flow or subflow to run it until the next breakpoint.
    -   Step over a breakpoint to run the flow or subflow without pausing at the next breakpoint.
    -   Step into a subflow to debug the subflow in a separate tab.
    -   Step out of subflow to return to the debug tab of the parent flow.
    -   Skip all breakpoints to resume running the flow or subflow without pausing at any breakpoints.
-   **3. Show Action Details**

    Option to show or hide the configuration details, output data, and steps run information for all flow steps. Turn on this option to show action details for all flow steps. Turn off this option to only show action details for the current flow step.

-   **4. Debugging state**

    Indicates which step of the flow or subflow you're currently debugging.

-   **5. Breakpoints**

    Set a breakpoint to pause the flow at this step. Remove a breakpoint to run the flow without pausing on a step.

-   **6. Modify inputs button**

    Open the Modify Inputs panel to temporarily change an input's configuration value.

-   **7. Runtime and configuration values**

    View the runtime and configuration values generated by the current step. Use these values to determine if the flow generates the data you expect it to.


\[Omitted image "example-flow-debugger-step-into-subflow.png"\] Alt text: Subflow stepped into from main flow

When you step into a subflow, Workflow Studio displays a separate tab to debug the subflow.

-   **8. Subflow debug tab**

    Step into a subflow to debug it in a separate browser tab.


## Modify input values

Override the configured value of a paused step to determine how the flow behaves with a new value. Modifying configuration values allows you to test the flow without editing it. You can determine which configuration values enable the flow to run, and which configuration values produce unexpected or undesired results.

\[Omitted image "example-flow-debugger-modify-input-value.png"\] Alt text: Modify the Message input of a Log action

You can only modify the value of the current step that the debugger has paused on. Enter a new value and save your changes.

-   **1. Modify Inputs button**

    The **Modify Inputs** button is unavailable when the Modify Inputs panel is already open.

-   **2. Input that you want to modify**

    Enter or select a new value for the input.

-   **3. Original value**

    See the original configuration values for the inputs.

-   **4. Save modifications**

    Save the configuration input values for the current debug session.


\[Omitted image "example-flow-debugger-modified-inputs.png"\] Alt text: Modified runtime values for a Log and Look Up Records action

After you modify a value, use the debug controls to resume the flow to run the step. Look at the step execution details to see both the original configuration value and the modified runtime value.

-   **1. Runtime value for Log action**

    The runtime value of the Log action was changed to be `Modified log message`.

-   **2. Configuration value for Log action**

    The current configuration value of the Log action remains `Original log message`.

-   **3. Runtime value for Look Up Records action**

    The runtime value of the Look Up Records action was changed to be `3`.

-   **4. Configuration value for Look Up Records action**

    The current configuration value of the Look Up Records action remains `1000`.