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

# First request

This guide walks through everything needed to make your first successful call to the Relaybase API.

## 1. Get an API key

If you haven't already, [create an account](/getting-started/create-account) and [generate an API key](/getting-started/create-api-key) from the Relaybase dashboard. Copy it somewhere safe it's only shown once.

## 2. Authenticate your request

Relaybase uses Bearer token authentication. Every request needs an `Authorization` header:

```http theme={null}
Authorization: Bearer rb_key_<token>
```

See [Authentication](/getting-started/authentication) for details.

## 3. Call the validation endpoint

Send a `POST` request to `/v1/email/single-validate` with the email you want to check:

```bash theme={null}
curl -X POST https://api.tryrelaybase.com/v1/email/single-validate \
  -H "Authorization: Bearer rb_key_<token>" \
  -H "Accept: application/json" \
  -d '{"email": "user@example.com"}'
```

## 4. Read the response

```json theme={null}
{
  "data": {
    "catch_all": false,
    "is_disposable": false,
    "is_free": true,
    "is_role_based": false,
    "is_valid": true,
    "mx_valid": true,
    "reason": "Mailbox verified via SMTP",
    "result": "jane@company.com",
    "score": 85,
    "smtp_code": 250,
    "status": "valid",
    "suggestion": "Email appears fully deliverable",
    "syntax_valid": true
  },
  "message": "result",
  "status": 200,
  "success": true
}
```

`status` tells you the overall classification (`valid`, `invalid`, or `risky`), and `score` gives you a 0–100 deliverability confidence signal. See [Validation Results](/concepts/validation-results) for what each field means.

## Next steps

<CardGroup cols={2}>
  <Card title="Validation Results" icon="circle-check" href="/concepts/validation-results">
    Understand the classification and scoring model.
  </Card>

  <Card title="Rate Limits" icon="gauge" href="/concepts/rate-limits">
    Avoid getting rate limited when validating many emails.
  </Card>
</CardGroup>