Build a Google Chat app with a Gemini Enterprise AI agent

This page explains how to build a Google Workspace add-on that works in Google Chat and interfaces with a Gemini Enterprise AI agent.

Note: In Google Chat, add-ons appear to users as Google Chat apps. You can also build your Chat app using Google Chat API interaction events. To learn more, see the Extend Google Chat overview.

AI agents autonomously perceive their environment, reason, and execute complex, multi-step actions to achieve a defined goal. In this tutorial, you use the Idea Generation agent provided by default by Google that helps with innovation and problem-solving for enterprise users.

The following diagram shows the architecture and messaging pattern:

In the preceding diagram, a user interacting with a Chat app implemented with a Gemini Enterprise AI agent has the following flow of information:

1. A user sends a message to a Chat app, either in a direct message or in a Chat space.
2. The Chat app logic that's implemented either in Apps Script or as a web server with HTTP endpoints receives and processes the message.
3. The Gemini Enterprise AI agent receives and processes the interaction.
4. Optionally, the Chat app or AI agent can integrate with Google Workspace services, such as Calendar or Sheets, or other Google Services, such as Google Maps or YouTube.
5. The Chat app asynchronously sends responses using the Google Chat API to communicate the AI agent progress.
6. The responses are delivered to the user.

Objectives

• Set up your environment.
• Deploy the Chat app.
• Configure the Chat app.
• Test the Chat app.

Prerequisites

• A Business or Enterprise Google Workspace account with access to Google Chat.
• A Google Cloud project with billing enabled. To check that an existing project has billing enabled, see Verify the billing status of your projects. To create a project and set up billing, see Create a Google Cloud project.
• A Gemini Enterprise app set up with Google Identity as identity provider.

Set up your environment

Turn on the Chat API

Before using Google APIs, you need to turn them on in a Google Cloud project. You can turn on one or more APIs in a single Google Cloud project.

In the Google Cloud console, enable the Google Chat API.

Enable the API

Configure the OAuth consent screen

All apps using OAuth 2.0 require a consent screen configuration. Configuring your app's OAuth consent screen defines what is displayed to users and app reviewers, and registers your app so you can publish it later.

1. In the Google Cloud console, go to Menu > Google Auth platform > Branding.

   Go to Branding

2. If you have already configured the Google Auth platform, you can configure the following OAuth Consent Screen settings in Branding, Audience, and Data Access. If you see a message that says Google Auth platform not configured yet, click Get Started:
1. Under App Information, in App name, enter a name for the app.
2. In User support email, choose a support email address where users can contact you if they have questions about their consent.
3. Click Next.
4. Under Audience, select Internal.
5. Click Next.
6. Under Contact Information, enter an Email address where you can be notified about any changes to your project.
7. Click Next.
8. Under Finish, review the Google API Services User Data Policy and if you agree, select I agree to the Google API Services: User Data Policy.
9. Click Continue.
10. Click Create.
3. For now, you can skip adding scopes. In the future, when you create an app for use outside of your Google Workspace organization, you must change the User type to External. Then add the authorization scopes that your app requires. To learn more, see the full Configure OAuth consent guide.

Create a service account in Google Cloud console

Create a new service account with the role Discovery Engine User by following these steps:

Google Cloud console

1. In the Google Cloud console, go to Menu > IAM & Admin > Service Accounts.

   Go to Service Accounts

2. Click Create service account.
3. Fill in the service account details, then click Create and continue.
   Note: By default, Google creates a unique service account ID. If you would like to change the ID, modify the ID in the service account ID field.
4. Optional: Assign roles to your service account to grant access to your Google Cloud project's resources. For more details, refer to Granting, changing, and revoking access to resources.
5. Click Continue.
6. Optional: Enter users or groups that can manage and perform actions with this service account. For more details, refer to Managing service account impersonation.
7. Click Done. Make a note of the email address for the service account.

gcloud CLI

1. Create the service account:

   gcloud iam service-accounts create SERVICE_ACCOUNT_NAME \
     --display-name="SERVICE_ACCOUNT_NAME"

2. Optional: Assign roles to your service account to grant access to your Google Cloud project's resources. For more details, refer to Granting, changing, and revoking access to resources.

The service account appears on the service account page.

Create a private key

Warning: This example uses an exported service account key for simplicity's sake. Exporting a private key is not recommended in production because it shouldn't be stored in an insecure location, such as source control.

To learn more about secure service account implementations and best practices, see Choose when to use service accounts.

To create and download a private key for the service account, follow these steps:

1. In the Google Cloud console, go to Menu > IAM & Admin > Service Accounts.

   Go to Service Accounts

2. Select your service account.
3. Click Keys > Add key > Create new key.
4. Select JSON, then click Create.

   Your new public/private key pair is generated and downloaded to your machine as a new file. Save the downloaded JSON file as credentials.json in your working directory. This file is the only copy of this key. For information about how to store your key securely, see Managing service account keys.

5. Click Close.

For more information about service accounts, see service accounts in the Google Cloud IAM documentation.

Create and configure the Chat app project

1. In the Google Cloud console, go to Menu > IAM & Admin > Settings.

   Go to IAM & Admin Settings

2. Note the Project number and Project ID fields.

3. Go to Gemini Enterprise:

   Open Gemini Enterprise

4. Note the Location and ID of the application.

5. Click the following button to open the GE AI Agent Quickstart Apps Script project.

   Open the project

6. Click Overview > Make a copy.

7. In your Apps Script project, click Project Settings > Edit script properties > Add script property to add the following script properties:

   1. REASONING_ENGINE_RESOURCE_NAME with the Gemini Enterprise app resource composed with the information noted in previous steps.

      projects/PROJECT_ID/locations/APP_LOCATION/collections/default_collection/engines/APP_ID
      

   2. SERVICE_ACCOUNT_KEY with the JSON key from the service account downloaded in previous steps such as { ... }.

8. Click Save script properties

9. In your Apps Script project, click Project Settings.

10. Under Google Cloud Platform (GCP) Project, click Change project.

11. In GCP project number, paste the Google Cloud project number noted in previous steps.

12. Click Set project. The Cloud project and Apps Script project are now connected.

Create a test deployment

You need a deployment ID for this Apps Script project, so that you can use it in the next step.

To get the head deployment ID, do the following:

1. In the Chat app Apps Script project, click Deploy > Test deployments.
2. Under Head deployment ID, click Copy.
3. Click Done.

Configure the Chat app

Using your Apps Script deployment, follow these steps to deploy the Google Chat app for testing:

1. In the console, search for Google Chat API, and click Google Chat API.
2. Click Manage.

3. Click Configuration and set up the Chat app:

   1. In the App name field, enter GE Quickstart.
   2. In the Avatar URL field, enter https://developers.google.com/workspace/add-ons/images/quickstart-app-avatar.png.
   3. In the Description field, enter GE Quickstart.
   4. Under Functionality, select Join spaces and group conversations.
   5. Under Connection settings, select Apps Script project.
   6. In the Deployment ID field, paste the Head deployment ID that you previously copied.
   7. Under Visibility, select Specific people and groups in your domain, and enter your email.

4. Click Save.

The Chat app is ready to respond to messages.

Test the Chat app

To test your Chat app, open a direct message space with the Chat app and send a message:

1. Open Google Chat using the Google Workspace account that you provided when you added yourself as a trusted tester.

   Go to Google Chat

2. Click New chat.
3. In the Add 1 or more people field, type the name of your Chat app.

4. Select your Chat app from the results. A direct message opens.

   Note: If you don't see your Chat app in the list of results, ensure that you've included your Google Workspace account in the Visibility settings of the Chat API Configuration page in the Google Cloud console.

5. In the new direct message with the app, type I need to find ideas! and pressenter.

   The Chat app replies with Default Idea Generation agent response.

To add trusted testers and learn more about testing interactive features, see Test interactive features for Google Chat apps.

Troubleshoot

When a Google Chat app or card returns an error, the Chat interface surfaces a message saying "Something went wrong." or "Unable to process your request." Sometimes the Chat UI doesn't display any error message, but the Chat app or card produces an unexpected result; for example, a card message might not appear.

Although an error message might not display in the Chat UI, descriptive error messages and log data are available to help you fix errors when error logging for Chat apps is turned on. For help viewing, debugging, and fixing errors, see Troubleshoot and fix Google Chat errors.

Clean up

To avoid incurring charges to your Google Cloud account for the resources used in this tutorial, we recommend that you delete the Cloud project.

Caution: Deleting a project has the following effects:

• Everything in the project is deleted. If you used an existing project for this tutorial, when you delete it, you also delete any other work you've done in the project.
• Custom project IDs are lost. When you created this project, you might have created a custom project ID that you want to use in the future. To preserve the URLs that use the project ID, such as a URL on appspot.com, delete the selected resources inside the project instead of deleting the whole project.

If you plan to explore multiple tutorials and quickstarts, reusing projects can help you avoid exceeding project quota limits.

1. In the Google Cloud console, go to the Manage resources page. Click Menu > IAM & Admin > Manage Resources.

   Go to Resource Manager

2. In the project list, select the project you want to delete and then click Delete .
3. In the dialog, type the project ID and then click Shut down to delete the project.

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• Integrate fundamental AI concepts in Chat apps
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