Install Plug-in Composer

Install Plug-in Composer as an IntelliJ IDEA extension and authenticate to your Appian site before you build plug-ins. This page covers the prerequisites, deploying the Plug-in Composer (Appian Site) plug-in to your site, installing the extension in IntelliJ IDEA, and signing in to your Appian site. For an overview of what Plug-in Composer is and the plug-in types it generates, see Plug-in Composer.

Prerequisites for using Plug-in Composer

Using Plug-in Composer requires the following in your local development environment:

• IntelliJ IDEA: Plug-in Composer is an IntelliJ IDEA extension. IntelliJ IDEA 2026.1.1 or higher is required.
• Java: Java 17 or higher is needed to build, compile, and package generated plug-ins.
• Gradle: Gradle version 9.6.0 or higher is required to build and package generated plug-ins.
• Access to an Appian site: You must be able to authenticate to an Appian site with your site credentials. The site must be on Appian 26.9 and have the Plug-in Composer (Appian Site) plug-in deployed.

Deploy the Plug-in Composer (Appian Site) plug-in

Plug-in Composer needs a connection to your Appian site to interact with AI services. This connection is created and maintained by the Plug-in Composer (Appian Site) plug-in, which authenticates requests between your Appian Cloud site and IntelliJ IDEA.

To deploy the Plug-in Composer (Appian Site) plug-in on your site:

1. In the Admin Console, click Plug-ins.
2. On the Plug-ins page, click ADD NEW PLUG-INS.
3. Search for Plug-in Composer (Appian Site).
4. Select the checkbox on the plug-in row.
5. Click DEPLOY.

Install Plug-in Composer in IntelliJ IDEA

Download the Plug-in Composer IDE extension from the Appian AppMarket, then install it in IntelliJ IDEA from disk.

To install Plug-in Composer:

1. Download the Plug-in Composer IDE extension from the Appian AppMarket.
2. In IntelliJ IDEA, go to Settings (Preferences on macOS), or press Ctrl+Alt+S.
3. Select Plug-ins in the left pane.
4. Click the gear icon at the top of the Plug-ins page and select Install Plug-in from Disk.
5. Select the downloaded plug-in archive and click OK.
6. Restart IntelliJ IDEA when prompted so the extension activates.

Authenticate to your Appian site

Before you generate a plug-in, you must sign in to your Appian site. Plug-in Composer authenticates every request with your Appian site credentials over Transport Layer Security (TLS) and rejects unauthenticated requests.

To sign in to your Appian site:

1. In the Plug-in Composer tool window, enter your Appian site connection details.
2. Submit the credentials to authenticate.

If authentication fails, Plug-in Composer returns an error that identifies the cause:

• Invalid credentials: The credentials you entered were not accepted by the Appian site. Confirm your username and password, then try again.
• Unreachable site: Plug-in Composer could not reach the Appian site. Confirm the site URL and your network connection.
• Missing site plug-in: The Appian site does not have the Plug-in Composer (Appian Site) plug-in deployed. Contact your site administrator.

After you sign in to your Appian site, you can generate, enhance, and fix plug-ins. For task instructions, see Build with Plug-in Composer.

Feedback