Hypermail MCP Server - Connect Claude, Cursor & AI Assistants to Your Email Account

What is MCP?

The Model Context Protocol is an open standard that lets AI assistants call external tools. Hypermail publishes an MCP server that turns your account into a set of tools your assistant can use.

Instead of writing API calls by hand, you describe what you want. Your assistant picks the right Hypermail tool, fills in the parameters, and shows you the result. Ask it to list your campaigns, pull open rates, pause a send, add a subscriber, or check whether an address is deliverable.

The server runs on Hypermail infrastructure over Streamable HTTP. Every request carries your API key, and the Hypermail API enforces exactly the same permissions it does for any other integration.

Plain-language control - Manage campaigns, lists, subscribers, and verification by asking.
27 ready-made tools - Campaigns, lists, subscribers, messages, replies, domains, sending profiles, clients, users, and email verification.
Full API reach - A call_api tool reaches more than 160 additional API actions across 11 areas.
Hosted for you - Nothing to install, build, or keep running.
Your key is the boundary - Every call is authorized by your API key. Delete the key to revoke access.

How It Works

Three steps and you are talking to your account.

1

Get your API key

Log in to Hypermail and go to API → Get API Key. Create a dedicated key for your assistant rather than reusing an existing one.

2

Add the URL to your client

Paste the server URL with your key into Claude Desktop, Claude Code, Cursor, or Codex. Setup snippets for each are below.

3

Ask in plain language

Your assistant discovers the Hypermail tools automatically. Ask for campaign stats, list changes, or a verification and it does the rest.

Connect Your Client

The server URL is the same for every client. Replace YOUR_API_KEY with your Hypermail API key.

Paste your API key to personalize the snippets below (optional) Your key stays in your browser. This page never sends it anywhere.

Server URL

https://hypermailsystem.com/mcp.php?api_key=YOUR_API_KEY

Prefer to keep the key out of the URL? Send it as a header instead: Authorization: Bearer YOUR_API_KEY

Claude Desktop

Open Settings → Connectors → Add custom connector.
Name it Hypermail and paste this URL:

https://hypermailsystem.com/mcp.php?api_key=YOUR_API_KEY

Save, then fully quit and reopen Claude Desktop.

Claude Code

Run once in your terminal:

claude mcp add --transport http hypermail "https://hypermailsystem.com/mcp.php?api_key=YOUR_API_KEY" --scope user

Or keep the key out of the URL with a header:

claude mcp add --transport http hypermail https://hypermailsystem.com/mcp.php --scope user --header "Authorization: Bearer YOUR_API_KEY"

Cursor

Add to ~/.cursor/mcp.json, or use Settings → MCP → Add new global MCP server:

{
  "mcpServers": {
    "hypermail": {
      "url": "https://hypermailsystem.com/mcp.php?api_key=YOUR_API_KEY"
    }
  }
}

Codex CLI

codex mcp add hypermail --url "https://hypermailsystem.com/mcp.php?api_key=YOUR_API_KEY"

Other MCP clients

Any client that supports remote MCP servers over Streamable HTTP will work. Point it at the server URL above and authenticate with either the api_key query parameter or an Authorization: Bearer header. The endpoint is stateless, so no session handling is required.

Available Tools

27 tools your assistant can call. List tools accept start and limit for pagination (up to 1,000 records per call).

Read reads data only Write changes data Destructive deletes, sends, or spends credits

Campaigns

Tool	What it does	Type
get_campaigns	List email campaigns with status and basic stats.	Read
get_campaign_detail	Get full detail for a single campaign by id.	Read
get_campaign_results	Per-recipient results for a campaign. Filter to delivered, soft bounces, or hard bounces.	Read
pause_campaign	Pause a sending campaign by id.	Write
resume_campaign	Resume a paused campaign by id.	Write
create_campaign	Create and schedule a campaign from a list, message, subject, and from details. This schedules a real send.	Destructive
delete_campaign	Delete a campaign by id.	Destructive

Lists & Subscribers

Tool	What it does	Type
get_lists	List your email lists, optionally within a parent folder.	Read
get_list_detail	Get a list and its emails by list id, optionally filtered by status.	Read
get_subscribers	List subscribers, optionally for one list.	Read
create_list	Create a list seeded with one or more emails, as newline-separated addresses or a CSV with an email column.	Write
add_email_to_list	Add one address to a list, with optional custom field values.	Write
delete_list	Delete a list by id.	Destructive

Messages & Replies

Tool	What it does	Type
get_messages	List saved email messages and templates.	Read
get_replies	List inbound replies.	Read
get_unsubscribe_list	List globally unsubscribed and suppressed emails.	Read

Sending Setup

Tool	What it does	Type
get_domains	List sending domains on the account.	Read
get_sending_profiles	List sending (from) profiles.	Read
get_email_account_info	Account-level email info: credits, plan, and counters.	Read

Clients & Users

Tool	What it does	Type
get_clients	List client and sub-accounts under your account.	Read
change_auto_renew	Enable or disable auto-renew for a client account.	Write
get_users	List the users on your account with name, username, email, and last login.	Read

Email Verification

Tool	What it does	Type
verify_email	Verify the deliverability of one email address. Rate-limited to one address per second.	Write

Discovery & Full API Access

Tool	What it does	Type
list_areas	List every API area and how many actions each has. The place to start exploring.	Read
list_actions	List the actions in an area with their classification and HTTP method.	Read
describe_action	Get the classification, method, and handler for one area/action pair.	Read
call_api	Invoke any non-hidden API action by area and action with a map of parameters. Use the curated tools when one exists and this for everything else.	Varies

Everything Else via call_api

The curated tools cover the everyday work. For the long tail, call_api reaches every public action in the Hypermail API. Your assistant can use list_areas and list_actions to find what is available.

email · 90 actions sms · 24 actions leads · 12 actions listverify · 12 actions data · 8 actions datafinder · 5 actions clients · 4 actions home · 4 actions api · 3 actions support · 3 actions ai · 1 action

Try Prompts Like These

List my campaigns and show the open rate for the most recent one.

Create a list called Spring Prospects and add jane@example.com.

Pause campaign 123 and tell me how many emails were delivered so far.

Is bob@example.com a deliverable address?

Which of my sending domains are set up, and how many credits do I have left?

Safety & Limits

Treat your API key like a password. Anyone with it can act on your account. Create a dedicated key for your assistant and delete it to revoke access at any time.

Your key is the access boundary. The MCP server forwards your key to the Hypermail API, which enforces the same permissions it does for every integration. Nothing can happen that your key could not already do.
Destructive tools are labeled. Deletes, scheduled sends, and purchases carry a destructive flag so clients can ask before running them, and Hypermail can switch them off at the server level.
Keys are never echoed. Tool output and error messages redact your API key.
Standard API limits apply. Email verification is throttled to one address per second, and list tools return at most 1,000 records per call.
Stateless by design. Each request is independent. There are no sessions to hijack and nothing is stored on the server between calls.

Troubleshooting

Symptom	Fix
401 Unauthorized or “API key required”	The key is missing or mistyped. Check the `?api_key=` value, or generate a fresh key under API → Get API Key.
Tools do not appear in the client	Fully quit and reopen the app. Confirm the URL is exactly the one shown above.
“Refused: … destructive action”	Destructive tools have been disabled on the server. Use the Hypermail web app for that action, or contact us.
Slow or timed-out calls	Large result sets take longer. Ask your assistant to paginate with `start` and `limit`.

Endpoint: https://hypermailsystem.com/mcp.php · Transport: MCP Streamable HTTP (stateless) · Protocol versions: 2024-11-05, 2025-03-26, 2025-06-18 · Auth: api_key query parameter or Authorization: Bearer header · Health check: ?health=1

MCP FAQ

What is the Model Context Protocol (MCP)?

MCP is an open standard that lets AI assistants call external tools and data sources. Hypermail publishes an MCP server so assistants such as Claude, Cursor, and Codex can manage campaigns, lists, subscribers, and email verification in your account.

Do I need to install anything?

No. The server is hosted by Hypermail. Add the server URL and your API key to your AI client and the tools appear automatically.

Is it safe to give my AI assistant a Hypermail API key?

Treat the key like a password. Create a dedicated key for your assistant, pass it in an Authorization header when your client supports it, and delete the key to revoke access. Destructive tools are flagged so clients can ask for confirmation, and the key is never echoed in tool output.

Which AI clients are supported?

Claude Desktop, Claude Code, Cursor, Codex CLI, and any client that supports remote MCP servers over Streamable HTTP.

Does the MCP server cost extra?

The MCP server sits in front of the Hypermail API and uses your existing account, plan, and API key. Actions that consume credits, such as email verification or sending, count the same way they would through the API.

Ready to connect your AI assistant?

Get Your API Key

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