Draft Emails with Zapier and Google Vertex AI

Using Zapier with Google Vertex AI, you can automatically draft polished emails based on data that moves through your apps, such as form submissions, support tickets, or CRM updates.

This how-to guide walks you through connecting Google Vertex AI in Zapier and creating a workflow that drafts an email you can send or refine later.

What You Need Before You Start in Zapier

Before building your automation, make sure you have access to the required accounts and permissions.

A Zapier account with permission to create Zaps.
A Google Cloud project with Vertex AI enabled.
Access to at least one text generation model in Google Vertex AI (for example, Gemini models, depending on your setup).
The app that will trigger your Zap, such as a form tool, CRM, or help desk platform.

If you need additional automation strategy help beyond this tutorial, you can explore consulting resources such as Consultevo.

Connect Google Vertex AI to Zapier

To draft an email with Google Vertex AI, you must first connect your Google Cloud project to Zapier.

In your Zapier account, go to the editor to create or edit a Zap.
Click the step where you want to add Google Vertex AI (usually after your trigger step).
Search for Google Vertex AI in the app search box and select it.
Choose the Generate Content or similar action, depending on the current options available in the Google Vertex AI app in Zapier.
When prompted to connect an account, select Connect a new account.
Follow the Google authorization flow, selecting the Google account and project that contains your Vertex AI models.
Grant Zapier the requested permissions so it can access the Vertex AI API on your behalf.

After authorization, your Google Vertex AI account will be available as a connected app inside Zapier.

Set Up a Trigger for Your Email Draft Zapier Workflow

Your Zap begins with a trigger that provides the information needed to compose the email draft.

In the Zap editor, choose your trigger app (for example, a form tool, CRM, e-commerce platform, or help desk).
Select a trigger event, such as New Form Submission, New Lead, or New Ticket.
Connect your account for that app and test the trigger to pull in sample data.

This sample data will help you configure the Google Vertex AI step in Zapier so that the model can draft an email using real-world fields like name, email address, and message content.

Configure the Google Vertex AI Action in Zapier

Next, configure the Vertex AI action that will actually write the email draft.

In the Zap editor, click the action step that uses Google Vertex AI.
Confirm the correct connected Google Vertex AI account and project.
Select the model you want to use for drafting emails, such as a text or chat model supported in the integration.
Configure the main input field (often called Prompt or Input) where you describe the email you want created.

Within Zapier, you can insert dynamic fields from your trigger so that the Vertex AI prompt includes specific details from each event.

Designing the Prompt in Zapier for High-Quality Email Drafts

The prompt is the most important part of your setup, because it tells Google Vertex AI what kind of email to generate.

When crafting your prompt in Zapier, consider including:

Goal of the email: sales follow-up, support response, confirmation, or internal update.
Audience: customer, lead, internal team member, or partner.
Tone: professional, friendly, concise, or detailed.
Required structure: subject line, greeting, body, call to action, and sign-off.
Key variables from your trigger: name, company, product, issue description, or previous messages.

An example of a structured prompt you might use in Zapier:

“Write a concise, friendly email response to a customer support inquiry. Use the customer’s name and summarize their issue. Propose a clear solution and invite them to reply if the problem continues. Include a subject line and a professional sign-off. Customer name: {{Name}}. Customer message: {{Message}}.”

Replace {{Name}} and {{Message}} with the actual fields inserted from your trigger in the Zapier editor.

Optional: Adjust Model Settings in Zapier

Depending on the current options in the Google Vertex AI app in Zapier, you may be able to adjust parameters such as:

Temperature (creativity vs. consistency).
Maximum tokens (maximum length of the generated email).
Top P or other advanced sampling settings.

Use lower creativity for formal transactional emails and slightly higher creativity for marketing or outreach emails.

Test the Email Draft Step in Zapier

Always test the integration before turning your automation on.

Click Test or Test step on the Google Vertex AI action inside Zapier.
Zapier will send the sample data from your trigger to the Vertex AI model using the prompt you configured.
Review the output in the test results. You should see a drafted email with a subject and body text.

If the draft does not meet your expectations, adjust the prompt or model settings in Zapier, then run another test until the result matches your desired style and structure.

Send or Store the Drafted Email from Zapier

Once you have a good draft, decide what should happen next in your workflow.

Option 1: Send the Email Automatically

You can add another step in Zapier to send the drafted email via your preferred email service.

Add a new action step after the Google Vertex AI step.
Choose your email app, such as Gmail, Outlook, or another provider.
Select an action like Send Email.
Map the drafted subject and body fields from the Vertex AI output into the email fields in Zapier.
Insert the recipient email address from your trigger data.
Test the step to confirm the email is sent correctly.

Option 2: Save the Draft for Manual Review

If you prefer to review drafts before sending, configure Zapier to store the generated email instead of sending it immediately.

Save the draft to your email provider as a draft message.
Store the text in a document or note-taking app for later editing.
Log the draft in your CRM or ticketing system as an internal note.

This approach keeps humans in the loop while still using automation to produce consistent initial drafts.

Turn On Your Zapier Automation

After testing all steps and confirming the drafted emails look good, you can activate your automation.

Give your Zap a clear name that indicates it drafts emails with Google Vertex AI.
Toggle the Zap switch to On.
Monitor the first few live runs in Zapier to ensure everything works as expected.

Troubleshooting Your Zapier and Google Vertex AI Setup

If your Zap does not behave as expected, review these common issues:

Missing or incorrect fields: Confirm that all mapped fields from your trigger exist and contain sample data.
Unsatisfactory email quality: Refine your prompt, provide clearer instructions, or adjust model settings in Zapier.
Authorization errors: Reconnect your Google Vertex AI account and verify you are using the correct Google Cloud project.
Delivery issues: If using an email-sending step, confirm the email provider connection and check spam folders.

For more details, review the official help article on drafting an email with Google Vertex AI in Zapier at this Zapier support page.

Next Steps with Zapier and Vertex AI

Once your first draft-email workflow is running, you can expand your use of Google Vertex AI in Zapier to support additional processes such as:

Summarizing long customer messages before drafting replies.
Generating follow-up emails based on past interactions.
Personalizing outreach emails using CRM data.
Creating internal status updates from support tickets or project updates.

By combining Google Vertex AI with the automation capabilities of Zapier, you can reduce manual writing, keep your email communication consistent, and respond faster to customers and leads.

Need Help With Zapier?

Work with ConsultEvo — a

Zapier Certified Solution Partner

helping teams build reliable, scalable automations that actually move the business forward.

Get Zapier Help