Posta MCP Server

An MCP (Model Context Protocol) server that exposes the Posta email API as tools for AI assistants.

Setup

go build -o posta-mcp .

Configuration

The server requires two environment variables:

Variable	Description
POSTA_BASE_URL	Your Posta instance URL (e.g. https://posta.example.com)
POSTA_API_KEY	API key generated from your Posta workspace

Usage

{
  "mcpServers": {
    "posta": {
      "command": "/path/to/posta-mcp",
      "env": {
        "POSTA_BASE_URL": "https://posta.example.com",
        "POSTA_API_KEY": "your-api-key"
      }
    }
  }
}

You can also run it with go run during development:

{
  "mcpServers": {
    "posta": {
      "command": "go",
      "args": ["run", "/path/to/mcp-server"],
      "env": {
        "POSTA_BASE_URL": "https://posta.example.com",
        "POSTA_API_KEY": "your-api-key"
      }
    }
  }
}

Tools

send_email

Send a single email.

Parameters:

Name	Type	Required	Description
from	string	yes	Sender email address
to	string[]	yes	Recipient email addresses
subject	string	yes	Email subject line
html	string	no	HTML body
text	string	no	Plain-text body
headers	object	no	Custom email headers
list_unsubscribe_url	string	no	List-Unsubscribe header URL
list_unsubscribe_post	boolean	no	Enable one-click unsubscribe
send_at	string	no	ISO 8601 datetime to schedule the email

send_template_email

Send an email using a pre-defined template.

Parameters:

Name	Type	Required	Description
template_id	number	no	Template numeric ID (preferred)
template	string	no	Template name (fallback)
language	string	no	Template language variant
from	string	no	Sender email address
to	string[]	yes	Recipient email addresses
template_data	object	no	Key-value data rendered into the template

send_batch

Send batch emails to multiple recipients using a template.

Parameters:

Name	Type	Required	Description
template_id	number	no	Template numeric ID (preferred)
template	string	no	Template name (fallback)
language	string	no	Default language for all recipients
from	string	no	Sender email address
recipients	array	yes	List of { email, language?, template_data? } objects

get_email_status

Get the delivery status of a sent email.

Parameters:

Name	Type	Required	Description
email_id	string	yes	The email UUID

Returns: status, error message (if any), retry count, timestamps.

retry_email

Retry sending a failed email. Only emails with status failed can be retried.

Parameters:

Name	Type	Required	Description
email_id	string	yes	The email UUID to retry

License

This project is licensed under the Apache License 2.0. See LICENSE for details.

---

Copyright

Copyright © 2026 Jonas Kaninda