How to send email from Claude.

27 March 2026 · 5 min read · By George Hartley

A step-by-step guide to sending campaigns, transactional messages, and automated flows directly from your terminal. No dashboard. No context switching. Just Claude and your email infrastructure.

I've been building email platforms for over a decade now, and I still hate switching tabs to send a campaign. You're in the terminal, you're in the zone, everything is flowing. Then some marketing task pulls you into a browser, a dashboard, a drag-and-drop editor. By the time you've found the right template, you've forgotten what you were working on ten minutes ago.

That tab-switching tax is exactly why we built MCP email into nitrosend. With Claude Code MCP, you can send email from Claude Code directly. Campaigns, transactional messages, automation flows, contact management. All from the terminal. No dashboard required.

What you need

Two things. That's the whole list.

1. A nitrosend account. The free tier includes unlimited contacts, up to 1,000 emails per month, and full MCP access. No credit card. Sign up at app.nitrosend.com/join.

2. Claude Code installed. If you're reading this, you've probably already got it. If not, grab it from Anthropic's docs. Any recent version with MCP support will do.

Step 1: Add the nitrosend MCP server

One command. Seriously.

$ claude mcp add nitrosend -- npx -y @nitrosend/mcp

Done. This installs the nitrosend MCP bridge, a lightweight Node.js process that translates between Claude's MCP protocol and the nitrosend API. It drops 16 tools into Claude's toolkit, covering everything from firing off a single transactional email to building multi-step automation flows with conditional branching.

Step 2: Sign in

First time you use the MCP email tools, Claude triggers an OAuth flow. A browser window pops up, you sign in (or create an account), and that's it. Credentials are stored securely. You won't need to do it again.

Once authenticated, Claude can see your contacts, templates, campaigns, and configuration. Everything is scoped to your account and your API key, so there are no surprises about permissions.

Step 3: Send your first email

Open Claude Code and type something like this.

Send a test email to [email protected] with the subject
"Hello from Claude" and a short welcome message.

Claude calls the nitro_send_message tool and fires off a transactional email directly. No campaign setup, no audience targeting. One email, one recipient, sent immediately.

You can watch the tool call in your terminal output, with the recipient, subject, and body all visible. The email lands in seconds. If you'd rather preview first, ask Claude for a dry run and it'll validate everything without actually sending.

Beyond transactional: campaigns and flows

Sending a single email is the warm-up. The real fun starts with campaigns (one-time sends to a list or segment) and flows (automated sequences triggered by events like signups or purchases).

Creating a campaign.

Create an email campaign called "March Product Update".
Send it to all subscribed contacts. Subject: "What's new
in March". Include sections about our new API, improved
deliverability, and the new template editor. Professional
tone, keep it concise.

Claude creates the campaign, composes the email with proper sections, sets the audience targeting, and leaves it in draft for your approval. Review it, send a test, approve the send. All from the terminal. I tested this flow about four hundred times while building nitrosend (which, honestly, might explain why my test inbox has 11,000 unread messages).

Creating an automation flow.

Build a welcome flow for new signups. Send a welcome
email immediately, wait 2 days, then send a tips email.
If they haven't opened the first email, send a
re-engagement email instead of the tips email.

Claude builds the entire flow graph. Trigger on new contact, send the welcome email, wait step, conditional split checking open status, both branches wired up with the right emails. The flow is created as a draft so you can review and activate when you're ready.

The killer onboarding prompt

This is the prompt I keep coming back to when demoing nitrosend. If you're setting up email for a new project, try it.

I'm setting up email for [yoursite.com]. Scrape my site
to set up the brand (colors, fonts, logo). Then create a
welcome flow for new signups: welcome email immediately,
a value-add email after 2 days, and a conversion email
after 5 days. Match my brand style.

Claude scrapes your website, pulls out brand colours, fonts, and your logo. It configures your nitrosend brand profile so every email matches your site's look. Then it builds a complete 3-email welcome sequence, each email designed in your brand style, spaced out over the first week after signup.

Zero to a fully branded, multi-step email onboarding flow in about 90 seconds.

When I first saw this work end to end on an early nitrosend build, I remember thinking we'd accidentally made every email template editor redundant (we hadn't, but it felt like it at the time).

What else can you do?

The nitrosend Claude Code MCP server exposes 16 tools. Beyond sending emails and building flows, you can manage contact lists and segments, set up and verify sending domains, review email content with spam scoring, pull delivery analytics, configure sender defaults and reply-to addresses, and import contacts from inline data or CSV files. The full platform is accessible through natural language prompts.

The shift is worth noting. You're not learning a new dashboard or memorising where buttons live. You describe what you want, and Claude handles the rest. If you can explain your email strategy in plain English, you can send email from Claude Code and have it running in minutes.

We're adding new MCP tools regularly, so if there's something you wish Claude could do with your email, there's a fair chance we're already building it. Or just tell us and we will.


Want to send your first email from Claude? nitrosend is the AI-native email platform. Start free.