MCP Server

Connect PostStack to AI assistants like Claude, Cursor, and Windsurf through the Model Context Protocol. Send emails, manage contacts, and control your email infrastructure using natural language.

What is MCP? The Model Context Protocol is an open standard that lets AI assistants call external tools. The PostStack MCP server exposes 72 tools covering the full API — no code required, just configure your client and start prompting.

Setup

No install needed — the server runs directly via npx. Pick your client below and add the configuration. You will need a PostStack API key from the dashboard.

Claude Desktop

Add to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json on macOS, %APPDATA%\Claude\claude_desktop_config.json on Windows):

json

{
  "mcpServers": {
    "poststack": {
      "command": "npx",
      "args": ["-y", "@poststack.dev/mcp"],
      "env": {
        "POSTSTACK_API_KEY": "sk_live_..."
      }
    }
  }
}

Claude Code

Add PostStack as an MCP server directly from the terminal:

bash

claude mcp add poststack -e POSTSTACK_API_KEY=sk_live_... -- npx -y @poststack.dev/mcp

Cursor / VS Code

Add to your editor's MCP configuration:

json

{
  "poststack": {
    "command": "npx",
    "args": ["-y", "@poststack.dev/mcp"],
    "env": {
      "POSTSTACK_API_KEY": "sk_live_..."
    }
  }
}

Self-hosted? Set the POSTSTACK_BASE_URL environment variable to point to your own instance:

bash

POSTSTACK_BASE_URL=https://mail.yourdomain.com

Available Tools

Once connected, your AI assistant has access to the full PostStack API across 13 resources:

Resource	Tools
Emails	Send, batch send, list, get, cancel, reschedule
Domains	Create, list, get, verify DNS, update settings, delete
Contacts	Create, list, search, get, update, delete, unsubscribe
Templates	Create, list, get, update, delete, publish, unpublish, duplicate
Broadcasts	Create, list, get, update, send, cancel
Webhooks	Create, list, get, update, delete
Segments	Create, list, get, update, delete, add/remove contacts
Subscription Topics	Create, list, delete, get/add/remove contact subscriptions
Contact Properties	Create, list, update, delete custom properties
Suppressions	List, add, remove
API Keys	Create, list, get, revoke
Inbound Emails	List, get, list attachments, reply, forward
Mailboxes	Create, list, get, update, delete, change password

Example Prompts

With the MCP server connected, you can ask your AI assistant to:

“Send a welcome email to alice@example.com from hello@mydomain.com”

Compose and send emails with natural language

“List all my domains and check which ones are verified”

Inspect your sending infrastructure

“Create a contact segment called "beta-users" and add these contacts to it”

Organize contacts into audiences

“Show me all bounced emails from the last 7 days”

Monitor deliverability and troubleshoot issues

“Create a webhook that notifies my endpoint when emails are delivered”

Wire up event-driven integrations

“Set up a new mailbox support@mydomain.com”

Manage email hosting through conversation

Permissions

The MCP server authenticates using your API key. You can control what the assistant is allowed to do by choosing the right key type:

`full_access`

All 72 tools enabled — send emails, manage domains, contacts, templates, webhooks, and everything else.

`sending_access`

Restricted to sending emails only. Use this when you want the assistant to compose and send but not modify your account.

Create and manage API keys in the dashboard. See Authentication for more details.

Source Code

The MCP server is open source and built on the PostStack TypeScript SDK. View the source on GitHub.