> ## Documentation Index
> Fetch the complete documentation index at: https://onecli.sh/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Resend: Transactional Email for AI Agents

> Send transactional emails and check delivery status via the Resend API. API keys injected by the gateway automatically.

## Overview

OneCLI connects AI agents to Resend using an API key. Agents can send transactional emails, check delivery status, and manage contacts. The gateway injects the API key into requests to the Resend API automatically.

This is useful for agents that need to send notifications, alerts, or reports by email without configuring SMTP.

## Setup

<Steps>
  <Step title="Create an API key in Resend">
    Go to [resend.com/api-keys](https://resend.com/api-keys) and create a new API key. Choose the appropriate permission level (sending access or full access). Copy the key.
  </Step>

  <Step title="Connect in OneCLI">
    Open the OneCLI dashboard, go to **Connections** > **Resend**, and paste your API key.
  </Step>
</Steps>

## What agents can do

* Send emails with specified from address, recipients, subject, and HTML or plain text body
* Send emails with attachments
* Check the delivery status of a sent email (delivered, bounced, complained)
* List sent emails and their statuses
* Manage contacts and audiences (create, list, update, delete contacts)
* Send batch emails to multiple recipients
* Use verified domains for sending

## Controlling access with rules

Use OneCLI's [rules engine](/guides/rules) to limit what agents can do with Resend. For example, you can rate limit email sends to prevent accidental spam, or restrict the "from" address agents can use. Rules are evaluated before credential injection, so a blocked request never reaches Resend.