Mailpuff Integrations: AI Agents, Email Delivery and APIs

Mailpuff is a free WordPress newsletter plugin that connects to other software in five ways. AI agents such as Claude and ChatGPT run it over MCP. PostShiba, Mailyard or your SMTP plugin deliver the email. The Subscribe API adds people from other sites and apps. CSV import brings your list over from Mailchimp, Substack, beehiiv, Kit and others. Developers extend it with WordPress actions and filters.

This page maps every integration and links to the guide for each one.

Which integrations does Mailpuff support?

Mailpuff works on its own. Every integration below is optional and free.

Integration	What it does	What you need	Guide
AI agents (MCP)	An AI app writes, tests, schedules and reports on your campaigns	Saddle or the MCP Adapter plugin	Connect an AI agent
PostShiba	Delivers your email, checks your domain, warms it up and reports bounces	A PostShiba account	Sending services
Mailyard	Sends through Amazon SES, Postmark, Resend, Brevo, Mailgun or any SMTP server	The free Mailyard plugin	Sending services
Other SMTP plugins	Mailpuff hands each email to WordPress and your plugin delivers it	The SMTP plugin you already run	Sending services
Subscribe API	Adds a subscriber from another site, form or script with one HTTP request	The API key in Mailpuff’s settings	Subscribe API
CSV import	Moves your list from another newsletter tool and maps its columns	An export file	See below
WordPress hooks	Lets your own plugin react to subscribers, sends, opens and clicks	A plugin or theme of your own	Hooks reference

How do AI agents connect to Mailpuff?

AI agents connect to Mailpuff through an MCP server running on your own WordPress site. Mailpuff registers 40 tools with the WordPress Abilities API, and the server offers them to any AI app that speaks the Model Context Protocol. You can use Saddle, which adds access levels and approvals, or the plain WordPress MCP Adapter.

Once connected, you can ask for things in plain words: “Write a newsletter about our spring sale and send me a test,” or “How did last Tuesday’s email do?” The agent does the work with Mailpuff’s tools, on your site, with your data.

Mailpuff itself runs no AI model and never contacts an AI company. Read how to connect an AI agent, the full tool list, and what an agent can and can’t do.

Which email services can Mailpuff send through?

Mailpuff’s built-in route is PostShiba, a delivery service built for newsletters that Mailpuff connects to directly. For Amazon SES, Postmark, Resend, Brevo, Mailgun or a plain SMTP server, install the free Mailyard plugin. An SMTP plugin you already use keeps working. Your host’s PHP mail is the last fallback.

With PostShiba, Mailpuff shows the DNS records for your domain, warms up a new domain over 14 days, keeps to your plan’s limits, and stops mailing addresses that bounce or complain. The sending services guide covers each route.

How do I add subscribers from another app?

Send a POST request to the Subscribe API with the subscriber’s email and your API key in the X-Mailpuff-Key header. Mailpuff adds the person, or tags them if they are already on your list. It never re-subscribes anyone who unsubscribed or bounced. The Subscribe API guide has examples in cURL, PHP and JavaScript.

Can I move my list from Mailchimp, Substack or Kit?

Yes. Export your subscribers as a CSV file and upload it under Mailpuff → Subscribers → Import. Mailpuff recognizes exports from Mailchimp, Substack, beehiiv, Kit, MailerLite, FluentCRM and Groundhogg and maps their columns for you.

Each subscriber keeps a record of when and how they agreed to hear from you. Addresses another service marked as erased are skipped. An AI agent can also import up to 500 people per call with the import-contacts tool, as long as it states how they agreed.

What does Mailpuff connect to inside WordPress?

• The Newsletter signup block. Add it to any page or post. New signups confirm by email (double opt-in), and a honeypot, a timer and rate limits stop bots. The form works on cached pages.
• Comment and registration forms. Mailpuff can add a signup checkbox to the WordPress comment form and the registration form.
• Privacy tools. Subscribers are included in the WordPress personal data export and erase tools.
• Avatars. The subscriber list uses your WordPress avatar settings, so Gravatar loads only when you have avatars turned on.

How can developers extend Mailpuff?

Mailpuff fires WordPress actions when subscribers are added, confirmed or change status, when a campaign sends, and when someone opens an email or clicks a link. Filters let you change each message before it goes out, add audience types and adjust sending limits.

Other mail plugins can report bounces to Mailpuff with the mailpuff_bounce action. The hooks reference lists every hook with its arguments and examples.

Does Mailpuff send my data anywhere?

Mailpuff sends no data to PlugPress. It loads no remote fonts and makes no license or usage calls. It talks to outside services only in three cases: PostShiba once you connect it, Gravatar when avatars are on, and YouTube for a video thumbnail when an email has a Video block without your own image.

When you connect an AI app, that app receives what its requests return, such as subscriber details or campaign results, under its own terms. Connect only apps you trust.

FAQ

Do I need Saddle to use Mailpuff?

No. Mailpuff works fully from the WordPress admin. Saddle is one of two ways to connect an AI agent, and the other is the MCP Adapter plugin.

Does Mailpuff work with Zapier or Make?

There is no dedicated app for either. Any automation tool that can send an HTTP POST request with a custom header can add subscribers through the Subscribe API.

Does Mailpuff sync WooCommerce customers?

Not today. You can import a customer CSV with a note on how they agreed to get email, or call the Subscribe API from your own checkout code.

Is there an outgoing webhook when someone subscribes?

Not as a setting. Developers can hook mailpuff_contact_created or mailpuff_contact_status_changed and send the data wherever they need it. The hooks reference has an example.

Related guides

• Connect an AI agent to Mailpuff with MCP
• Mailpuff MCP tools reference
• Send Mailpuff email through PostShiba, Mailyard or SMTP
• Mailpuff hooks reference