The Email Triage Agent — Never Sort Your Inbox Manually Again

Step-by-step guide to building the workflow that saves 1.5 hours every week — with free tools, exact prompt and complete settings.

The average professional receives 120 emails per day and spends 15-20 minutes every morning sorting them by priority before they can start real work. The Email Triage Agent eliminates this entirely. Here is exactly how to build it.

What This Agent Does

Every email that arrives in your Gmail inbox is automatically read by ChatGPT, classified into one of four categories — URGENT, REPLY, FYI or SPAM — and labelled accordingly before you even open your inbox. You open your email to find it already sorted, every morning, without touching a thing.

Setup time: 20-30 minutes. Running cost on free tiers: zero. Time saved: 1.5 hours per week minimum.

What You Need Before Starting

A Gmail account (free). A Zapier account (free tier: 100 tasks/month, sufficient for most inboxes). A ChatGPT account (free tier works). Create your four Gmail labels first: go to Gmail settings, create labels called Urgent, Reply, FYI and Spam.

Step 1: Create Your Zap

Log into Zapier. Click Create → New Zap. In the Trigger section, search for Gmail. Select "New Email in Gmail" as the trigger event. Connect your Gmail account via the OAuth flow. In the trigger settings, select All Mail as the mailbox. Test the trigger — Zapier will pull in a recent email to confirm the connection works.

Step 2: Add the ChatGPT Action

Add a new Action step. Search for ChatGPT. Select "Send Message." Connect your OpenAI account. In the User Message field, paste exactly this prompt, mapping the Gmail email body to the {email body} placeholder:

You are an expert email prioritisation assistant. Read the email below and classify it as one of: [URGENT — respond within 2 hours] [REPLY — respond within 24 hours] [FYI — no response needed] [SPAM — unsolicited]. Return ONLY the category label followed by a one-sentence reason. No other text. Email: {email body}

Step 3: Add the Gmail Label Action

Add another Gmail action: "Apply Label to Email." In the Label field, you need to map the ChatGPT output to the correct label. Use Zapier's Formatter tool to extract the first word of the ChatGPT response (URGENT, REPLY, FYI or SPAM) and map it to the corresponding label you created.

Step 4: Test Thoroughly Before Going Live

Send yourself five test emails of different types: a genuine urgent meeting request, a newsletter, a sales email, a simple FYI update, and an obvious spam message. Check that each one is correctly classified and labelled. If classification is wrong on any type, adjust the prompt — add more examples or clarify edge cases in the LIMITS section.

Going Live and What to Monitor

Turn the Zap on. Monitor your inbox for the first week. Check the Zapier task history daily to confirm the workflow is running without errors. If you receive an unusual volume of emails on certain days, check that the free tier 100-task limit is not being hit (upgrade to Starter at $19.99/month if needed).

After the first week of reliable operation, you will never want to sort email manually again.