How to Set Up an Email-Powered AI Agent Workflow with Resend

Step-by-step guide to giving your AI agent email capabilities — read, send, and automate responses using Resend and the Agent Email Inbox skill. Total setup: about 10 minutes.

What We’re Building#

By the end of this tutorial, your AI agent will be able to read incoming emails, send replies, and trigger automated actions based on what arrives in your inbox. You won’t need to leave your terminal or switch to Gmail.

This setup uses Resend’s agent skills and MCP server, so your agent talks to email the same way it talks to your file system — through structured commands.

What You Need#

• An AI agent that supports skills (Claude Code, Cursor, Codex, or Grok)
• Node.js 18+ with npx available
• A Resend account with a verified domain (free tier works)
• About 10 minutes

Let’s go.

Step 1: Create a Resend Account and Verify a Domain#

Resend is an email API built for developers. It handles delivery so you don’t have to mess with SMTP servers or spam filters.

Sign up at resend.com — the free tier includes 100 emails per day and inbound email processing, which is plenty for testing.

After signing up:

1. Go to the Domains tab
2. Click Add Domain and enter a domain you control
3. Add the three DNS records Resend gives you (TXT, MX, CNAME) to your DNS provider
4. Wait for verification — it usually takes 2-5 minutes

While you wait, you can move to the next step.

Step 2: Install the Resend Skills#

Open your terminal and run:

npx skills add resend/resend-skills

The CLI shows you a list of available skills from the package:

? Select skills to install (use arrow keys / space to toggle):
❯ ◻ resend (11474 installs) — Resend email API
  ◻ agent-email-inbox (4685 installs) — Secure email inbox for AI agents
  ◻ resend-cli (4389 installs) — Operate Resend from the terminal
  ◻ react-email (4098 installs) — Build HTML emails with React
  ◻ email-best-practices (4298 installs) — Guidance for deliverable emails

Select at least resend (for sending) and agent-email-inbox (for reading). The CLI writes the skill files into your agent’s skill directory automatically.

Step 3: Authenticate with OAuth#

This is where Resend’s setup beats every other email integration I’ve tried. Instead of generating an API key and setting environment variables, you authenticate once through OAuth.

Start your agent and trigger the email skill. In Claude Code, you can just ask:

Check my email inbox

On first use, your agent detects the MCP server configuration and opens a browser window to Resend’s OAuth page. Sign in with your Resend account, approve the access request, and you’re done.

The OAuth token is cached locally. You won’t need to re-authenticate unless you revoke access on Resend’s side.

Step 4: Read Your First Email#

Once authenticated, you can ask your agent to read emails. Try these commands:

Show me the last 5 emails in my inbox

Read the most recent email and summarize it

Find any emails from the last 24 hours with "verification" in the subject

Your agent queries the Resend MCP server, fetches the matching messages, and returns them in your chat. No context switching. No opening a browser tab.

Here’s what I saw when I tried it:

Agent: I found 3 emails in your inbox from the last 24 hours:

1. "Verify your Resend domain" — Resend Team (2 hours ago)
   Status: Pending verification, click the link to complete setup

2. "Your order #12345 has shipped" — Shopify (5 hours ago)
   Status: Shipped, tracking number included

3. "Weekly newsletter" — Substack (8 hours ago)
   Status: Read, no action needed

The agent parsed subject lines, senders, and time stamps from the raw email data. It even identified which ones needed action — something Gmail’s web interface doesn’t do without filters.

Step 5: Send Email from Your Agent#

Reading email is useful. Sending email from your agent is where it gets powerful.

Send an email to [email protected] with subject "Daily standup notes"
and body: Here are today's notes:
- Finished the API integration
- Started work on the dashboard
- No blockers

Your agent picks up the resend skill, formats the email, and sends it through Resend’s API. The email lands in the recipient’s inbox like any normal message — proper DKIM signing, SPF records, the works.

You can also attach context from your current session:

Read the email from [email protected] about the project timeline.
Then reply to it with a summary of what I've worked on this week.
Get the week's git commits from the current repo first.

This is the chain I use most often: read incoming email → gather context from my current work → compose and send a reply. All in one shot.

Step 6: Build an Automated Workflow#

The real payoff is combining read and send into automated workflows. Here’s a practical example — auto-responding to support emails:

Every hour, check my inbox for new emails with "Support" in the subject.
For each one:
1. Read the full email
2. Categorize it as "bug report", "feature request", or "general question"
3. Draft a response acknowledging receipt
4. Log the ticket to my project tracker

Show me the log after processing.

Your agent loops through the steps without you touching anything. The same pattern works for:

• Order confirmations → extract tracking numbers → log to a spreadsheet
• Newsletter digests → summarize → append to a reading list
• Invoice emails → extract amounts → update a budget tracker
• Slack notification emails → forward action items to a task list

You set the rules once, and your agent follows them.

Step 7: Schedule Recurring Checks#

For hands-off operation, schedule your agent to check email on a timer. In Claude Code, you can write a simple script your agent runs periodically:

Create a script that checks my inbox every 30 minutes for urgent emails
(marked "urgent" or from my manager's address). If found, notify me
with a summary in the terminal.

Your agent creates the check script and can run it on whatever schedule makes sense. No Zapier subscription required.

Troubleshooting#

Next Steps#

Once you have basic email automation running, try these extensions:

• Add react-email for beautiful HTML templates in your automated emails
• Combine with a search skill to research and email findings automatically
• Use email as a trigger for other agent workflows — when a specific email arrives, kick off research, scrape a page, or update a database

The agent-email-inbox and resend skills turn your agent into a proper email client. Not just a writer that drafts messages for you to send manually — a full participant in your email workflow.

For more agent skill tutorials and intros, visit topaiskills.com. Check out the Agent Email Inbox skill intro for details on all available Resend agent skills.