How We Scored Email Tools for Dots
A dot is only as useful as what it can reach. We gave each platform points in five areas:
| Area | What earned points |
|---|---|
| Connection | A directory plugin or a hosted MCP server a dot can use from OpenAI's cloud |
| Write coverage | Drafts, templates, segments, and sequences the dot can prepare, not just read |
| Events | MCP events that wake the dot when something happens |
| Program depth | Campaigns and sequences, consent, suppressions, and outcome reporting |
| Approval fit | Draft and test states that line up with Custom Rules and OpenAI's built-in reviews |
Directory plugins win on setup time. They do not automatically win on depth, which is why a custom plugin can rank above them.
Events Change What a Dot Is For
Most email assistants are reactive: you ask, they answer. A dot connected to a platform with MCP events can be proactive.
OpenAI documents MCP events for dots: the server lists events, the dot subscribes, and deliveries arrive by webhook. Sequenzy publishes these:
| Event | Fires when |
|---|---|
| email.replied | A subscriber replies to an email you sent |
| email.bounced | An email bounces |
| email.complained | A recipient marks an email as spam |
| subscriber.created | A subscriber is added from any source |
| subscriber.unsubscribed | A subscriber unsubscribes |
| campaign.sent | A campaign finishes sending |
| sequence.finished | A subscriber reaches the end of a sequence |
| subscriber_import.completed | An import finishes |
A practical first subscription is email.replied filtered to your onboarding sequence. Replies to onboarding emails are often buying signals or bug reports, and a dot can bring each one to you with the subscriber's context attached.
Add Sequenzy to Your Dot
- In ChatGPT, open Plugins and choose to add a custom MCP server.
- Name it Sequenzy and enter https://api.sequenzy.com/v1/mcp/openai.
- Create it as a plugin, sign in to Sequenzy, and choose what ChatGPT may do.
- Ask your dot to confirm the workspace with a read-only request.
The step-by-step dots setup guide covers Custom Rules, events, and troubleshooting.
Custom Rules for Email
Dots support four rule outcomes. A sensible starting set for email:
| Action | Rule |
|---|---|
| Read campaigns, stats, segments, replies | Take action without asking |
| Create or edit drafts and templates | Take action when you say so |
| Send tests to internal addresses | Ask before taking action |
| Send or schedule campaigns, activate sequences, bulk subscriber changes | Ask before taking action |
| Change plans, billing, or sending domains | Hand off to you |
Which Tool for Which Team
You want the dot to run the program with you: Sequenzy, for coverage and events.
You sell online and want answers fast: Klaviyo's directory plugin, moving to its MCP server when you want drafts.
Your email decisions depend on deals and accounts: HubSpot.
You want low cost and a directory install: Brevo.
You only need help with product email: Resend.
Sources and Verification Notes
We checked dots behavior against OpenAI's documentation: dots overview, computers and apps, controls, tasks and memory, MCP events, and connecting a custom MCP server. Plugin listings were checked on chatgpt.com/plugins in October 2026. Details about the Mailchimp and ActiveCampaign ChatGPT apps come from third-party reviews.
Vendor documentation:
- Sequenzy MCP and events
- Klaviyo MCP server
- HubSpot API overview
- Brevo developer documentation
- ActiveCampaign developer documentation
- Customer.io APIs
- Mailchimp: connect Mailchimp to ChatGPT
- Loops MCP server
- Resend API reference
- Postmark developer documentation
- Twilio SendGrid API reference
Plans, plugin catalogs, and write permissions change often. Look at what your own ChatGPT account and email platform show before handing a dot real subscribers.