Make SEO Fly: Automate Shopify Image Alt Text with AI + n8n (and Save $100 in App Fees)
Stop overpaying for image SEO apps—use AI + n8n to generate and update Alt Text automatically.
From this post on, we move into real n8n practice.
Here’s the teaching style for this series:
- I won’t over-explain every tiny feature with theory.
- I won’t use generic “daily life” demos (send a meaningless email, summarize meaningless info, etc.).
- I’ll use real Shopify business scenarios.
The goal is: one feature explanation + one real automation scenario each time. If a full scenario feels hard to digest in one go, treat that as the fuel for self-learning.
What this post covers / doesn’t cover
This post focuses on the most important first step: wiring up a Webhook (the Trigger). The next parts—filtering images without Alt Text, sending image + product info to AI, and writing the Alt Text back to Shopify—will be covered in the follow-up post.
1) The scenario
When a merchant uploads or updates products, there are often many images. Image Alt Text matters for SEO, so I want to use AI to generate Alt Text based on the image, and I want the whole thing to run automatically.
The end-to-end flow looks like this:
Detect product image updates (Webhook trigger)
Filter which images are missing Alt Text
Send image + product context to AI to generate specific, SEO-friendly Alt Text
Write the Alt Text back to Shopify automatically
Compared to typical image SEO apps that cost tens of dollars per month, this is cheaper—and more importantly, AI can generate more specific Alt Text by “understanding” the image instead of outputting generic rule-based copy.
2) What a Webhook (Trigger) is
A Webhook is a 24/7 “signal receiver”—similar to SMS or push notifications on your phone.
In a Shopify context, whenever something changes (new order, product update, inventory change, etc.), Shopify can “call” your system immediately so you can react automatically—no manual refreshing in admin.
You can also scope it down. For example, only fire a Webhook when a product gets updated. That’s why it’s the most important part of automation: the Trigger.
Webhooks are always two-sided
n8n provides the receiver URL; Shopify needs to “send” events to that URL.
3) How to set up Webhooks (n8n + Shopify)
Step 1: Create the Webhook receiver (n8n)
Create a Webhook node in n8n and name it however you like. You’ll get a URL—think of it as a dedicated phone number for receiving signals.
Step 2: Configure the sender (Shopify)
Now configure the event in Shopify. Using “Product Update” as an example, go to Settings → Notifications, find the behavior you want to monitor, and paste the Webhook URL you got from n8n.
Once that’s done: when you edit a product in Shopify admin and click Save, Shopify will send the signal to n8n immediately.
Test URL vs Production URL: don’t mix them up
| URL type | Used for | Notes |
|---|---|---|
| Test URL | Debugging while building | A dedicated Test URL for repeated testing |
| Production URL | Deploying for long-running automation | Used when the node should stay on 24/7 |
In practice: start with the Test URL while iterating, then switch Shopify’s target URL to the Production URL when you’re ready to run it continuously.
4) What’s next
In the next steps of the automation, we’ll process the incoming payload: clean and filter data, let AI generate Alt Text, validate AI output, then use HTTP requests to write results back to Shopify. Those parts are not the focus of this post.
Two related tutorials
If you haven’t set up n8n yet, start with One-Click Shopify Blog Automation with n8n + AI. For image SEO fundamentals, see The Ultimate Image SEO Guide: 3 Moves.
