How to integrate Unione MCP with Codex

Codex is one of the most popular coding harnesses out there. And MCP makes the experience even better. With Unione MCP integration, you can draft, triage, summarise emails, and much more, all without leaving the terminal or the app, whichever you prefer.

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Api Key

UniOne is an email delivery service with a flexible Web API and SMTP API for transactional and marketing emails. It streamlines reliable, scalable email sending for developers and businesses.

32 Tools

Introduction

Codex is one of the most popular coding harnesses out there. And MCP makes the experience even better. With Unione MCP integration, you can draft, triage, summarise emails, and much more, all without leaving the terminal or the app, whichever you prefer.

Also integrate Unione with

Why use Composio?

Apart from a managed and hosted MCP server, you will get:

  • CodeAct: A dedicated workbench that allows GPT to write its code to handle complex tool chaining. Reduces to-and-fro with LLMs for frequent tool calling.
  • Large tool responses: Handle them to minimise context rot.
  • Dynamic just-in-time access to 20,000 tools across 1000+ other Apps for cross-app workflows. It loads the tools you need, so GPTs aren't overwhelmed by tools you don't need.

How to install Unione MCP in Codex

Run the setup command

Run this command in your terminal to add the Composio MCP server to Codex.

Terminal

It will initiate the authentication in a browser window, authorize Codex to access your Composio account.

Composio authentication page

(Optional) Authenticate with OAuth

To authenticate manually, run the login command to open a browser window and authorize Codex to access your Composio account.

bash
codex mcp login composio

Verify the connection

Run codex mcp list to confirm Composio appears as a registered MCP server.

bash
codex mcp list

Codex App

Codex App follows the same approach as VS Code.

  1. Click ⚙️ on the bottom left → MCP Servers → + Add servers → Streamable HTTP:
  2. Fill the header and Key fields with { "x-consumer-api-key" = "ck_*******" }.
  3. The Key is the Composio API key, that you can find on dashboard.composio.dev
  4. Click on Authenticate and authorize Codex to your Composio account and you're all set.
Codex App MCP setup
  1. Restart and verify if it's there in .codex/config.toml
bash
[mcp_servers.composio]
url = "https://connect.composio.dev/mcp"
http_headers = { "x-consumer-api-key" = "ck_*******" }

What is the Unione MCP server, and what's possible with it?

The Unione MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Unione account. It provides structured and secure access to your Unione email delivery service, so your agent can send transactional or marketing emails, manage sending domains, monitor delivery events, check account balance, and automate email operations on your behalf.

  • Automated email sending and scheduling: Have your agent send transactional or marketing emails and even schedule deliveries right from your Unione account.
  • Domain verification and management: Easily manage sender domains, trigger domain verifications, and handle DNS/DKIM checks to keep your emails deliverable.
  • Event monitoring and export: Let your agent fetch specific email events, retrieve delivery metrics, or export comprehensive email event logs for auditing and analytics.
  • Account balance and plan checks: Quickly access your current email balance and subscription plan details, ensuring you stay within your sending limits.
  • Email job and pricing insights: Retrieve detailed information about specific email jobs and get up-to-date pricing for cost management before sending campaigns.

Conclusion

You've successfully integrated Unione with Codex using Composio's MCP server. Now you can interact with Unione directly from your terminal, VS Code, or the Codex App using natural language commands.

Key benefits of this setup:

  • Seamless integration across CLI, VS Code, and standalone app
  • Natural language commands for Unione operations
  • Managed authentication through Composio
  • Access to 20,000+ tools across 1000+ apps for cross-app workflows
  • CodeAct workbench for complex tool chaining

Next steps:

  • Try asking Codex to perform various Unione operations
  • Explore cross-app workflows by connecting more toolkits
  • Build automation scripts that leverage Codex's AI capabilities
TOOLS

Supported Tools

Every Unione action and event your agent gets out of the box.

Delete Event Dump

Tool to delete an event dump file and remove it from the queue or storage.

Delete Template

Tool to delete a template by ID.

Delete Webhook

Tool to delete a webhook event notification handler by its URL.

UniOne Email Balance

Tool to retrieve current account balance.

Cancel Scheduled Email

Tool to cancel a scheduled transactional email by its job ID.

UniOne Email Domain Management

Tool to manage sender domains in UniOne.

Get Email Event

Tool to retrieve details of a specific email event by its ID.

Get Email Send Job

Tool to retrieve detailed information about a specific email send job.

UniOne Email List (Export)

Tool to export email events within a specified time frame.

Resend Sent Email

Tool to resend a previously sent email by its job ID.

UniOne Email Resubscribe

Tool to resubscribe a recipient who previously unsubscribed.

Resume Paused Email

Tool to resume a paused transactional email by its job ID.

UniOne Email SMTP Configuration

Tool to retrieve SMTP server details and credentials.

UniOne Email Statistics

Tool to retrieve email sending statistics over a specified time range.

UniOne Email Unsubscribe

Tool to unsubscribe an email from future emails.

Batch Email Validation

Tool to validate multiple email addresses in a batch.

Remove Email from Suppression List

Tool to remove an email from the suppression list.

Retry Email Validation

Tool to retry an email validation request.

UniOne Email Webhook Types

Tool to retrieve supported email webhook event types.

Create Event Dump

Tool to create an asynchronous CSV event dump.

UniOne Event Dump List

Tool to retrieve the full list of event dumps.

Get Event Dump

Tool to retrieve the status and download URLs of an event dump.

Get Email Suppression Details

Tool to check if an email is suppressed and retrieve the reason and date.

Get Template

Tool to get template properties by ID.

Get Webhook Configuration

Tool to retrieve webhook configuration by its URL.

Schedule Email

Tool to schedule a transactional email up to 24 hours ahead.

Suppression List

Tool to return the suppression list since a given date.

Delete Tag

Tool to delete a specific tag.

UniOne Tag List

Tool to retrieve all user-defined tags.

UniOne Template List

Tool to list email templates.

Set Template

Tool to set or update an email template.

Set Webhook

Tool to set or edit a webhook event notification handler.

FAQ

Frequently asked questions

With a standalone Unione MCP server, the agents and LLMs can only access a fixed set of Unione tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Unione and many other apps based on the task at hand, all through a single MCP endpoint.

Yes, you can. Codex fully supports MCP integration. You get structured tool calling, message history handling, and model orchestration while Tool Router takes care of discovering and serving the right Unione tools.

Yes, absolutely. You can configure which Unione scopes and actions are allowed when connecting your account to Composio. You can also bring your own OAuth credentials or API configuration so you keep full control over what the agent can do.

All sensitive data such as tokens, keys, and configuration is fully encrypted at rest and in transit. Composio is SOC 2 Type 2 compliant and follows strict security practices so your Unione data and credentials are handled as safely as possible.

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