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

# email

> Transactional email

The `email` capability sends transactional emails through reliable email infrastructure.

## Providers

| Provider | Features                        |
| -------- | ------------------------------- |
| Resend   | Modern API, high deliverability |

## Basic Usage

```typescript theme={null}
const result = await saturn.email({
  to: 'user@example.com',
  subject: 'Welcome to our service',
  text: 'Thanks for signing up!',
});

console.log(result.data.messageId);
// → Unique message ID for tracking
```

## Parameters

<ParamField body="to" type="string | string[]" required>
  Recipient email address(es).
</ParamField>

<ParamField body="subject" type="string" required>
  Email subject line.
</ParamField>

<ParamField body="text" type="string">
  Plain text body.
</ParamField>

<ParamField body="html" type="string">
  HTML body (alternative to text).
</ParamField>

<ParamField body="from" type="string">
  Sender email address. Defaults to configured address.
</ParamField>

<ParamField body="replyTo" type="string">
  Reply-to address.
</ParamField>

## Response

```typescript theme={null}
interface EmailResponse {
  data: {
    messageId: string;  // Unique message ID
    status: string;     // 'sent', 'queued'
  };
  metadata: {
    chargedUsdCents: number;
    provider: string;
    latencyMs: number;
    auditId: string;
  };
}
```

## Examples

### HTML Email

```typescript theme={null}
const result = await saturn.email({
  to: 'user@example.com',
  subject: 'Your weekly report',
  html: `
    <h1>Weekly Report</h1>
    <p>Here's your summary for this week:</p>
    <ul>
      <li>Tasks completed: 15</li>
      <li>Hours logged: 40</li>
    </ul>
  `,
});
```

### Multiple Recipients

```typescript theme={null}
const result = await saturn.email({
  to: ['alice@example.com', 'bob@example.com'],
  subject: 'Team update',
  text: 'Important team announcement...',
});
```

### With AI-Generated Content

```typescript theme={null}
async function sendPersonalizedEmail(
  to: string,
  topic: string,
  context: string
) {
  // Generate email content with LLM
  const content = await saturn.reason({
    prompt: `Write a professional email about: ${topic}
    Context: ${context}
    Keep it concise and friendly.`,
  });

  // Send the email
  return saturn.email({
    to,
    subject: `Update: ${topic}`,
    text: content.data.content,
  });
}
```

## Pricing

| Provider | Cost                |
| -------- | ------------------- |
| Resend   | \~\$0.001 per email |

## Domain Configuration

<Warning>
  To send from your own domain, you'll need to configure DNS records (SPF, DKIM, DMARC). Contact support for custom domain setup.
</Warning>

By default, emails are sent from a Saturn-managed domain. For production use, configure your own sending domain for better deliverability.

## Best Practices

* Always include a plain text version for accessibility
* Keep subjects under 50 characters
* Don't send unsolicited emails (spam)
* Include unsubscribe options for marketing emails
* Test emails before sending to large lists