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

# POST /api/verify/check

> Verifies a one-time passcode against the user's identifier and returns a signed attestation that the registration endpoint accepts as proof of ownership.

Verifies an OTP code for the identifier. For email, the code is checked against DO-local SQLite; for SMS, it is checked against Twilio Verify.

## Request body

| Field        | Type     | Required | Description                   |
| ------------ | -------- | -------- | ----------------------------- |
| `identifier` | `string` | Yes      | Email address or phone number |
| `channel`    | `string` | Yes      | `"email"` or `"sms"`          |
| `code`       | `string` | Yes      | OTP code submitted by user    |

## Response (200)

```json theme={null}
{
  "ok": true,
  "verified": true,
  "attestation": {
    "identifier": "alice@example.com",
    "channel": "email",
    "verified_at": "2024-01-01T00:00:00Z",
    "expires_at": "2024-01-01T00:05:00Z",
    "registrar": "did:new:0x...",
    "signature": "0x..."
  }
}
```

When `verified` is `false`, `attestation` is absent and a `message` field describes the failure reason.

## Errors

| Code  | Condition                                              | Description           |
| ----- | ------------------------------------------------------ | --------------------- |
| `400` | `"Missing required fields: identifier, channel, code"` | Field absent          |
| `400` | `"Invalid channel. Must be \"sms\" or \"email\""`      | Unknown channel       |
| `502` | `ok: false`                                            | Upstream Twilio error |

## Attestation lifetime

The attestation is a signed JWT-like payload (HMAC-SHA256 keyed by `ATTESTATION_SIGNING_KEY`) that expires in 300 seconds (`ATTESTATION_TTL_SECONDS`). It is passed as `attestation` in the subsequent [`POST /api/dids`](/api-reference/registration/dids) call to prove ownership.