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

# Resend

> Send transactional emails, manage audiences, contacts, and domains — control your email infrastructure from Mantle

Connect your Resend API key and let your AI agents send transactional emails, manage audiences and contacts, create
templates, and configure sending domains — all from Mantle.

***

## What you unlock

<CardGroup cols={2}>
  <Card title="Transactional email" icon="envelope">
    Send single or batch emails through Resend — welcome messages, receipts, notifications, and more.
  </Card>

  <Card title="Audience management" icon="users">
    Create audiences, manage contacts, and organize segments for targeted communication.
  </Card>

  <Card title="Email templates" icon="file-code">
    Create, update, and publish email templates — manage your email design system from chat.
  </Card>

  <Card title="Domain management" icon="globe">
    Add sending domains, verify DNS records, and manage API keys for different services.
  </Card>
</CardGroup>

***

## Connect Resend

<Steps>
  <Step title="Open Settings → Integrations">
    In any workspace go to **Settings → Integrations** and select **Resend**.
  </Step>

  <Step title="Get your API key">
    Log in at [resend.com](https://resend.com), go to **API Keys**, and create a new API key with the permissions your
    agent needs.
  </Step>

  <Step title="Paste and connect">Paste the key into the **API Key** field and click **Connect**.</Step>
</Steps>

***

## Agent tools

Add Resend tools to agents that need them. Their access is limited by the connected key and selected tools.

### Emails

| Tool              | Description                                     |
| ----------------- | ----------------------------------------------- |
| Send email        | Send a single transactional email               |
| Send batch emails | Send multiple emails in a single request        |
| Retrieve email    | Get details and delivery status of a sent email |
| Cancel email      | Cancel a scheduled email before delivery        |
| List emails       | List sent emails with status filters            |

### Audiences & Contacts

| Tool            | Description                                   |
| --------------- | --------------------------------------------- |
| Create audience | Create a new audience for targeted emails     |
| List audiences  | List all audiences in your account            |
| Create contact  | Add a contact to an audience                  |
| Update contact  | Update contact details or subscription status |
| List contacts   | List contacts in an audience                  |

### Templates & Domains

| Tool             | Description                             |
| ---------------- | --------------------------------------- |
| Create template  | Create a new email template             |
| Publish template | Publish a template for use in sending   |
| List templates   | List all email templates                |
| Create domain    | Add a new sending domain                |
| Verify domain    | Verify DNS records for a sending domain |
| List domains     | List all configured sending domains     |

***

## Triggers

<Note>
  Automated triggers for Resend are not yet available. Triggers will be added in a future update — check back soon.
</Note>

***

## Example use cases

<AccordionGroup>
  <Accordion title="Send a quick notification email">
    Ask your agent to send an email to a specific address with a subject and body — it handles the API call and confirms
    delivery status. Great for one-off notifications or follow-ups.
  </Accordion>

  <Accordion title="Manage your contact list from chat">
    Add or update contacts in your audience without opening the Resend dashboard. Ask your agent to add a new subscriber
    or update an existing contact's metadata.
  </Accordion>

  <Accordion title="Check email delivery status">
    After sending a batch of emails, ask your agent to check the delivery status — it retrieves each email's status
    (delivered, bounced, complained) and summarizes the results.
  </Accordion>
</AccordionGroup>

***

## Troubleshooting

<AccordionGroup>
  <Accordion title="My API key isn't working">
    Verify the key was created at [resend.com/api-keys](https://resend.com/api-keys) and has the required permissions.
    Generate a fresh key if the current one doesn't work.
  </Accordion>

  <Accordion title="Emails aren't being delivered">
    Check that your sending domain is verified in Resend. Unverified domains will cause emails to fail. Use "List
    domains" and "Verify domain" to check and fix DNS configuration.
  </Accordion>

  <Accordion title="Batch send partially failed">
    Some emails in a batch may fail due to invalid addresses or rate limits. Use "Retrieve email" to check the status of
    individual emails and identify the failures.
  </Accordion>

  <Accordion title="Template changes aren't reflected">
    Templates must be **published** after changes. Use "Publish template" to make your latest edits available for
    sending.
  </Accordion>
</AccordionGroup>

***

<Card title="Back to Integrations" icon="plug" href="/integrations/overview">
  View all available integrations
</Card>