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# sms

> Send an MFA verification code via SMS.

Send an MFA verification code via SMS.

### Schema

```yaml
openapi: 3.1.0
info:
  title: API
  version: 1.0.0
paths:
  /api/relay/rest/mfa/sms:
    post:
      operationId: subpackageMultiFactorAuthentication_request_mfa_sms
      summary: Request MFA token via SMS
      description: >-
        Creates a multi-factor authentication request and sends its code to the
        destination by SMS. Use it when an application must verify possession of
        a text-capable phone number; save the returned request ID and submit the
        code to [Verify MFA
        token](/docs/apis/rest/multi-factor-authentication/verify-mfa-token).
        Use the voice-call operation when the recipient cannot receive SMS.


        #### Permissions


        The API token used to authenticate must have the following scope(s)
        enabled to make a successful request: _Management_.


        [Learn more about API scopes](/docs/platform/your-signalwire-api-space).
      tags:
        - subpackage_multiFactorAuthentication
      responses:
        '200':
          description: The request has succeeded.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/MfaResponse'
        '401':
          description: Access is unauthorized.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Types.StatusCodes.StatusCode401'
        '422':
          description: The request failed validation. See errors for details.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Types.StatusCodes.ValidationError'
        '500':
          description: An internal server error occurred.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Types.StatusCodes.StatusCode500'
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/MfaRequest'
tags:
  - name: subpackage_multiFactorAuthentication
servers:
  - url: https://%7BYour_Space_Name%7D.signalwire.com
    description: SignalWire API
components:
  schemas:
    MfaRequest:
      type: object
      properties:
        to:
          type: string
          description: The E164 number to use as the destination.
        from:
          type: string
          description: >-
            The E164 number from your account to use as the origin of the
            message. SignalWire will use a special verified number if not
            specified.
        message:
          type: string
          default: 'Your Personal Authorization Code is:'
          description: >-
            Specify a custom message to send before the token. The message must
            fit within one segment; either 160 characters or 70 characters when
            using non-GSM symbols.
        token_length:
          type: integer
          default: 6
          description: The number of characters in the token, from 4 to 20. Defaults to 6.
        valid_for:
          type: integer
          default: 3600
          description: >-
            The number of seconds the token is considered valid for. Defaults to
            3600, with a maximum of 604800.
        max_attempts:
          type: integer
          default: 3
          description: >-
            The number of allowed verification attempts, including the first
            one, from 1 to 20. Defaults to 3.
        allow_alphas:
          type: boolean
          default: false
          description: >-
            Set to true or false, whether to include letters or just numbers in
            the token. Defaults to false (numbers only).
      required:
        - to
      description: MFA request model.
      title: MfaRequest
    uuid:
      type: string
      format: uuid
      description: Universal Unique Identifier.
      title: uuid
    MfaResponse:
      type: object
      properties:
        id:
          $ref: '#/components/schemas/uuid'
          description: The MFA request ID. Save this for verification.
        success:
          type: boolean
          description: Whether the request was successfully queued.
        to:
          type: string
          description: The destination of the MFA request.
        channel:
          type: string
          description: Can be sms for a text message or call for a phone call.
      required:
        - id
        - success
        - to
        - channel
      description: MFA response model.
      title: MfaResponse
    TypesStatusCodesStatusCode401Error:
      type: string
      enum:
        - Unauthorized
      title: TypesStatusCodesStatusCode401Error
    Types.StatusCodes.StatusCode401:
      type: object
      properties:
        error:
          $ref: '#/components/schemas/TypesStatusCodesStatusCode401Error'
      required:
        - error
      description: Access is unauthorized.
      title: Types.StatusCodes.StatusCode401
    Types.StatusCodes.SpaceApiErrorItem:
      type: object
      properties:
        detail:
          type: string
          description: A description of what caused the error.
        status:
          type: string
          description: The HTTP status code.
        title:
          type: string
          description: A short summary of the error type.
        code:
          type: string
          description: The error code.
      required:
        - detail
        - status
        - title
        - code
      description: Details about a specific validation error.
      title: Types.StatusCodes.SpaceApiErrorItem
    Types.StatusCodes.ValidationError:
      type: object
      properties:
        errors:
          type: array
          items:
            $ref: '#/components/schemas/Types.StatusCodes.SpaceApiErrorItem'
          description: List of validation errors.
      required:
        - errors
      description: The request failed validation. See errors for details.
      title: Types.StatusCodes.ValidationError
    TypesStatusCodesStatusCode500Error:
      type: string
      enum:
        - Internal Server Error
      title: TypesStatusCodesStatusCode500Error
    Types.StatusCodes.StatusCode500:
      type: object
      properties:
        error:
          $ref: '#/components/schemas/TypesStatusCodesStatusCode500Error'
      required:
        - error
      description: An internal server error occurred.
      title: Types.StatusCodes.StatusCode500

```

## **Response Example**

### Response (200)

```json
{
  "id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
  "success": true,
  "to": "+15554422333",
  "channel": "call"
}
```

## **Example**

```typescript {9}
import { RestClient } from "@signalwire/sdk";

const client = new RestClient({
  project: "your-project-id",
  token: "your-api-token",
  host: "your-space.signalwire.com"
});

const result = await client.mfa.sms({
    to: "+15559876543",
    from: "+15551234567",
    message: "Your code is: {code}",
});
const requestId = result.id;
console.log("MFA request:", requestId);
```

> Send an MFA verification code via SMS.