What is Script Include in ServiceNow? A Complete Beginner’s Guide with Step-by-Step Examples

BillMartin · 3 weeks ago

What is Script Include in ServiceNow? A Complete Beginner’s Guide with Step-by-Step Examples

If you’re just starting with ServiceNow or looking to write cleaner code on the platform, you’ve probably heard the term “script include” tossed around. Maybe you’ve wondered what is script include in ServiceNow, how it works, and why it’s such a big deal for developers and admins. Good news: this guide answers all your questions in simple terms, with a hands-on example and practical tips.

Understand the concept, learn how to build your first script include, and see why this feature is a true workhorse for efficient ServiceNow development.

Understanding Script Include in ServiceNow

A script include in ServiceNow is a reusable piece of server-side JavaScript. Think of it as your personal toolbox or a utility belt. Instead of repeating the same code in different areas of your platform, you stick that logic in a script include and call it wherever needed. This approach saves time, cuts down on errors, and keeps your ServiceNow implementation running smoothly.

At its core, a script include acts like a custom class or object. Other parts of ServiceNow—like business rules, workflows, or other script includes—can use the code you store inside.

Why Use Script Includes?

Here’s what makes script includes so useful:

Centralized Logic: Write once, use everywhere.
Easy Maintenance: Change one script to update logic in multiple places.
Better Organization: Group related functions together, like common calculations or validations.
Faster Development: Save time by not rewriting code.

Key takeaway: A script include turns repetitive tasks into a single, reliable component you can use again and again.

Navigating Script Includes in the ServiceNow Interface

When you work in ServiceNow, everything starts with the Application Navigator (that menu on the left). To find script includes, just search for “script include” in the navigator’s search box.

You’ll see a list of all existing script includes—some created by ServiceNow itself, others made by developers and admins for custom workflows. As a system admin, you can view and create new script includes, helping you manage how your instance behaves.

Pro tip: Script includes work globally across most modules and applications inside ServiceNow. This means the same function you write for an ITSM (IT Service Management) process can be called from HR, Facilities, or any custom workflow. That’s a lot of flexibility.

The Parts of a Script Include

A script include isn’t complicated, but it follows a basic structure:

Name: A unique title, often ending with “Utils” or “Helper” to show it’s a utility.
Script: Your actual JavaScript code—functions, logic, calculations.
Accessible From: Controls if it’s available to all application scopes or just a specific one.
Client Callable: Lets client-side scripts (like UI actions or client scripts) call your server-side function using a special technique called GlideAjax.

Below is a simple script include structure:

var MyUtils = Class.create();
MyUtils.prototype = {
  initialize: function() {},
  hello: function(name) {
    return 'Hello, ' + name + ' from Script Include';
  }
};

How to Create a Script Include in ServiceNow: Step-by-Step

Let’s walk through creating a script include called “HelloWorldUtils” that returns a friendly greeting. Here’s an easy two-step process:

Step 1: Create the Script Include

In the Application Navigator, search for “Script Include” and open the module.
Click New to create a new script include.
Enter a unique name: HelloWorldUtils
Set “Accessible from” to All application scopes (if you want it available everywhere).
In the script section, paste or type:

var HelloWorldUtils = Class.create();
HelloWorldUtils.prototype = {
  initialize: function() {},
  sayHello: function(name) {
    return 'Hello, ' + name + ', from Script Include';
  }
};

Save your script include.

This script includes a single method, sayHello, which takes a name and returns a simple greeting.

Step 2: Test the Script Include with Scripts - Background

You don’t need a fancy UI to try your script include. ServiceNow provides the “Scripts - Background” tool for quick tests.

In the Application Navigator, search for “Scripts - Background.”
Enter the following code to test your script include:

var helloWorld = new HelloWorldUtils();
var message = helloWorld.sayHello('Service Developer');
gs.info(message);

Click Run Script.
Look for the output at the bottom of the screen. You should see: Hello, Service Developer, from Script Include

That’s it! You’ve just created and executed your own server-side JavaScript in ServiceNow. No page reloads or extra steps, just pure reusable code.

Where and How Can You Call a Script Include?

Script includes don’t just help with one-off functions—they power key workflows, automate routine tasks, and provide strong backend support for complex business rules.

You can call script includes from:

Other Script Includes (to share or extend logic)
Business Rules (for server-side automation)
Workflow Activities (for backend processes)
Client Scripts (using GlideAjax for server calls from client-side code)

Understanding GlideAjax

For client-side code to reach a server script include, ServiceNow uses GlideAjax. This lets you call server code from the browser, fetch the result, and update the UI without a full page refresh.

Here’s a quick view:

Client-side Server-side

Client Script	Script Include
GlideAjax sends request	Script Include runs
Callback receives result	Response sent

Using GlideAjax with script includes unlocks dynamic, responsive user interfaces that rely on server data.

Best Practices for Script Includes

Script includes are powerful, but a few habits help you avoid headaches later.

Use Descriptive Names: Make it easy for others to understand the purpose (“IncidentHelper”, “UserUtils”, etc.).
Limit Scope When Possible: If logic shouldn’t be used everywhere, limit access to a certain scope.
Keep Functions Small and Focused: Each method should do one thing well. This makes debugging and updates far easier.
Include Comments: Even simple notes about function behavior can save time for you and others later.
Secure Sensitive Logic: If the code handles passwords, validation, or permissions, restrict access and review regularly.

Script Includes vs. Other Server-Side Scripts

It’s easy to wonder: why use a script include when you can just copy the same code across business rules or UI actions? The answer is reusability and maintainability.

Feature Script Include Business Rule / UI Action

Purpose	Central reusable code logic	Specific automation per table/UI event
Where Used	Called from anywhere in the platform	Runs in response to record changes or UI
Maintenance	Easy, change one file	Hard, update many scripts separately
Reusability	High	Low

Summary: Use script includes for shared code, business rules for targeted record automation.

Real-World Example: Greeting Users with Script Includes

Imagine a ServiceNow instance with multiple apps—ITSM, HR, Facilities. Instead of writing a “hello” message generator in every module, you stick the logic in a script include once. Now, any area can use your sayHello function and display friendly greetings to users with one line of code.

This simple example scales up. Imagine business processes like escalations, company-specific customizations, or integrations. Script includes make that logic easily accessible and future-proof.

Tips for Debugging and Testing Script Includes

Bugs happen, even in small scripts. Here are helpful tips:

Use gs.info() or gs.error() to output messages in Scripts - Background.
Double-check for typos in script include names; ServiceNow is case-sensitive.
Always test with sample data before using in production.
Check access permissions if your script isn’t running as expected.

Want to Learn More? Resources for ServiceNow Developers

ServiceNow development offers so much beyond script includes. Exploring related topics will strengthen your skills and help you build powerful, maintainable solutions. Want to go further? Check out the full ServiceNow developer tutorial playlist on TechTalk with Bill for step-by-step lessons, real-world examples, and expert advice.

You’ll find:

In-depth explanations about ServiceNow scripting, permissions, and architecture
Hands-on demos for advanced topics
Sample projects and more

Final Thoughts

Script includes are the backbone of organized, efficient ServiceNow development. Put simply, they’re reusable building blocks that keep your code clean and scalable. Whether you’re automating business logic, integrating different apps, or simplifying future updates, script includes are your go-to resource.

ServiceNow developers and admins use script includes every day to create quick, reliable solutions that stand the test of time. Try building your own, follow the best practices, and keep growing your skills.

Ready to deepen your ServiceNow knowledge? Don’t forget to check out the developer playlist for more tutorials, and stay tuned for the next lesson!

If you found this post helpful, let others know by sharing it, and remember to subscribe for updates and support ongoing tutorials. Happy coding!