---
title: "Rule Verb Extension"
slug: "rule-extensions-using-rule-engine"
description: "This document shows users how to create and use a Rule Engine Extension. Rule Engine Extensions allow users the ability to create a Rule that may be embedded in another Rule. "
updated: 2025-06-13T15:50:29Z
published: 2025-06-13T15:50:29Z
---

> ## Documentation Index
> Fetch the complete documentation index at: https://documentation.decisions.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Rule Verb Extension

## Overview

The **Rule Engine** can be extended by developers to create custom **Rule verbs** that can be embedded into a**Statement Rule**.

These custom verbs can be created either through a [Flow](/v9/docs/flows) or **Statement Rule** and are anchored to the datatype used as inputs to these elements. When the datatype is selected in a Rule, the Rule Extensions will appear under the **Custom** header when choosing the verb.

---

## Creating a Rule Extension

To create a **Rule Extension**, in a Designer project, click on CREATE RULE. In the gallery, select **Rule Extension** and select either option to create a new Rule Extension. The name for the Rule Extension will become the name for the custom verb. Each Rule extension is further expanded in its respective section.

| Rule Extension Type | Differences |
| --- | --- |
| Sequential Rule Extension [Flow] | The Sequential Rule Extension Type allows custom rule verbs to be embedded in another Rule using a Flow. Selecting this option will open the Flow Designer, allowing for more customized logic through the use of a Flow |
| Rule Extension [Statement Rule] | The Rule Extension [Statement Rule] allows for custom rule verbs to be created using another Rule. |

![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2024-10-08_17h09_59.png)

---

## Rule Extension [Statement Rule]

The following example will create a **Rule Extension** that determines if the account executing the **Rule** contains admin and is part of the Testing Department.

1. Create a new Rule Extension using **Rule Extension [Statement Rule]**. Enter a Name and click Create.
2. The Rule Designer will open. Click SETUP INPUT DATA.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h10_45.png)
3. Define an input, then Save. For this example, the Account datatype was used. ![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2024-10-08_14h46_40.png)
4. Define the statements for the **Rule** using the input, then Save and close the Rule Designer.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h14_30.png)
5. Create a new Rule.
6. For Select Data Element, select an input that matches the inputs needed for the**Rule Extension.** In this case, it will be an Account. Click Next.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h17_25.png)
7. When picking the verb, under the **Custom** header, select the configured **Rule Extension**, then click DONE.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h18_26.png)
8. Select DONE due to no additional inputs being needed.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h19_10.png)
9. Select **Debug** in the **Action bar** to test the Rule. Selecting the **Rule Extension** in the debugger will display the results.

---

## Sequential Rule Extension [Flow]

The following example will create a **Rule Extension** using a [Rule Extension Flow](/v9/docs/about-flow-behaviors) to check if the account executing the **Rule** has an email address in a specific list.

1. Create a new **Rule Extension** using **Sequential Rule Extension [Flow****].**
2. Click the SETUP INPUT DATA action.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h21_25.png)
3. Define the input; for this example, a String named Email Address is used.  
![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2024-10-08_15h28_25.png)
4. Design a Flow that will be used to evaluate the Rule input. For this example, Add a **Create Data step.**
5. Define two inputs, a List of Strings labeled Email List and a Boolean-labeled output. ![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h40_20.png)
6. Under **Data > Texts** in the**Toolbox**, add a **String is in List** step to the workspace. Configure the step to use Email Addresses and Email Lists as inputs.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h43_19.png)
7. Add a Mapping step for each path to alter the output to either True or False.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h45_28.png)
8. Map the output value to the Result in the End step. Save and close the Flow Designer.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h47_03.png)
9. [Create a new Rule.](/v9/docs/create-rules)
10. Use an input that matches the configured datatype of the Rule Extension, in this case, a String. Select NEXT.
11. When picking the verb, under the **Custom**header, select the configured Rule Extension, then click NEXT.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h48_57.png)
12. Since no additional parameters are being passed, select DONE.![](https://cdn.document360.io/6ef8bcc1-6489-4486-9ad1-83acff7e5df0/Images/Documentation/2025-06-13_11h49_38.png)
13. Debug the **Rule**. The Rule will return either True or False depending on the Flow Result.

---

For further information on Rules, visit the [Decisions Forum](https://community.decisions.com/categories/Rules).