Claude Code Email Integration: The Easy Way to Add Email

Your project works. People can sign up, fill in a form or pay you. Now it needs to send email, and you'd rather that didn't turn into a project of its own.

A Claude Code email integration splits into two parts. Your part is short and happens once: sign up for an email service, verify your domain and connect the service to Claude Code. Claude Code's part is everything after that: the secret key, the sending code and every email your project sends.

This guide walks through both parts, then shows you how to check it all works and how to change things later. No coding needed. Every step is either a few clicks or a message to Claude Code.

What does a Claude Code email integration involve?

Adding email to your project involves three things: a service that delivers your emails, a way for your live project to use that service, and the emails themselves. The code Claude Code writes can decide when an email should go out, but it can't deliver one on its own.

The emails in question are transactional emails: messages your project sends automatically because someone did something, like signing up, resetting a password or paying. Here's every piece involved, and who takes care of it with SimpleSends:

The connector is an MCP server. MCP, short for Model Context Protocol, is an open standard created by Anthropic that lets AI tools like Claude Code connect to other services. Once SimpleSends is connected, Claude Code can work with it directly in the chat.

SimpleSends is built for people who build with Claude Code but don't write code. The first three pieces are yours. After that, you brief Claude Code in plain English and it does the rest.

Your part: sign up, verify your domain, connect

Your part takes a few minutes of clicking plus the domain step, and you only do it once. These steps work the same whether you use Claude Code in the desktop app or in your browser.

1. Sign up and set up your sending address. Create your account on the SimpleSends website and follow the steps there to set up the address your emails will come from, such as hello@yourcompany.com. To send from your own domain, this includes adding a few DNS records where your domain is registered. DNS records are settings that tell the internet how your domain works, and these ones prove you own it. Every email service asks for this step. Our guide to verifying a domain for email explains it in plain English. Sign-up happens on the website, not inside the Claude Code chat.

2. Add SimpleSends as a connector. In Claude Code, open Customize, then Connectors. Choose Add, then Add custom connector, and fill in:

   Field	What to enter
   Name	SimpleSends
   MCP server URL	https://mcp.simplesends.com/mcp

3. Log in when Claude prompts you. When Claude asks you to connect, log in with your SimpleSends account. This links your account to Claude Code without Claude ever seeing your password.

4. Tell Claude Code it's connected. Back in your Claude Code chat, send this message:

   I've connected SimpleSends for all transactional email.

   What to expect: Claude Code takes it from there, including adding what your project needs to send email.

That's your part done. If you'd like more detail on how connectors work, or what to do if one won't connect, see our guide to connecting an MCP server to Claude Code.

Claude Code's part: the key, the sending code and every email

From here, Claude Code does the building. You tell it what you want, the way you'd brief a developer or designer, and approve what it shows you.

The secret key. Your live project needs a secret key, a private code that lets it use SimpleSends. Developers call this an API key. Claude Code creates the key through the connector and adds it to your project, so you never copy or paste it. The key lives in a private settings file in your project, called a .env file, and in your hosting platform's settings as an environment variable, which is a private setting your live project can read. On Vercel, for example, environment variables are encrypted and safe for secrets, but a change only applies to new deployments. So after a key is added there, your site needs a fresh deploy. If anything needs doing in your hosting settings, Claude Code tells you exactly what and where.

The sending code. This is the small piece of code that tells SimpleSends "send this email to this person" at the right moment, such as straight after someone signs up. Claude Code writes it and connects each email to the moment it belongs to. Once your project is live, it sends real emails through SimpleSends on its own. Claude Code doesn't need to be open, and nothing goes through the chat.

Every email. Claude Code designs, writes, builds and changes every transactional email your project sends. A good first brief covers the whole set:

Please set up all the transactional emails my project needs. Start by listing the ones you'd suggest and when each one goes out. Then let's go through them one at a time. Show me each email and send me a test before you switch it on.

What to expect: Claude Code suggests a list, such as a welcome email, password resets and receipts, and waits for you to agree before it builds each one. You stay in charge of what your users receive.

For the full picture of planning, writing and sending every email, read our guide to transactional emails in Claude Code.

How do you check your email integration works?

Check it in three stages: a test email from the chat, a real run-through on your own site, and a look at the send logs. Do all three before real users rely on your emails.

1. Send a test from the chat. Swap in your own address:

Can you send a test email to [your email address] through SimpleSends? Make the subject "Test from my project" and add one line saying the connection works.

What to expect: The first time Claude Code uses SimpleSends, Claude may ask your permission. That's normal, so approve it. Claude Code then confirms the email was sent. Check your inbox.

2. Try it for real. Test emails from the chat prove the connection works. Your project's own emails prove the sending code works. Sign up to your own project with an address you can check, or fill in your own contact form, and see what arrives. Look for:

3. Ask Claude Code to check the send logs. If an email doesn't arrive, Claude Code can look it up for you:

I signed up with [your email address] a few minutes ago but no welcome email arrived. Can you check in SimpleSends whether it was sent and tell me what happened?

What to expect: Claude Code reads the send logs in SimpleSends and tells you in plain English whether the email went out. If it didn't, it helps you work out why, such as a typo in the address or an email that was never triggered.

Our email testing guide has a full pre-launch checklist, and how to check whether your emails actually sent covers the usual causes when one goes missing.

How do you change things later?

To change anything, ask Claude Code. Changing an email is a message, not a project.

Change the wording or design.

Our welcome email feels a bit stiff. Make it warmer and shorter, and change the button to say "Go to your dashboard". Send me a test first.

Add a new email.

When someone's free trial has three days left, I'd like to send them a friendly reminder with a link to upgrade. Show me a draft before you build it.

Send from a new address or domain. A new address on a domain you've already verified is a quick message to Claude Code. A new domain needs the DNS step again, which you do by following the steps on the SimpleSends website.

Get changes to real users. Some changes only reach your live site after a fresh deploy. If you're not sure whether one does, ask Claude Code before you test it on the live site.

Disconnect the connector. You can switch the connector off or remove it in Claude's Connectors settings at any time. This only stops Claude Code working with SimpleSends in the chat. Your live project keeps sending its emails, because it sends through SimpleSends directly. To stop an email reaching users, ask Claude Code to switch that email off.

Want a step-by-step walkthrough of your very first email? Our guide to sending emails from Claude Code covers it from start to finish.