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

# Create a sender

> Create a new sender identity. The sender must be associated with a verified domain that belongs to your account.



## OpenAPI

````yaml POST /senders
openapi: 3.1.0
info:
  title: SendKit API
  description: The SendKit API allows you to send transactional emails programmatically.
  version: 1.0.0
servers:
  - url: https://api.sendkit.dev
security:
  - bearerAuth: []
paths:
  /senders:
    post:
      tags:
        - Senders
      summary: Create a sender
      description: >-
        Create a new sender identity. The sender must be associated with a
        verified domain that belongs to your account.
      operationId: createSender
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/CreateSenderRequest'
      responses:
        '201':
          description: Sender created successfully
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Sender'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '422':
          $ref: '#/components/responses/ValidationError'
components:
  schemas:
    CreateSenderRequest:
      type: object
      required:
        - name
        - username
        - domain_id
      properties:
        name:
          type: string
          maxLength: 255
          description: The sender display name.
          example: John Doe
        username:
          type: string
          maxLength: 64
          description: >-
            The username part of the email address. May only contain letters,
            numbers, dots, underscores, percent signs, plus signs, and hyphens.
            Must be unique per domain.
          example: john
        domain_id:
          type: string
          format: uuid
          description: The ID of a verified domain that belongs to your account.
          example: 550e8400-e29b-41d4-a716-446655440000
        reply_to:
          type:
            - string
            - 'null'
          format: email
          maxLength: 255
          description: The reply-to email address.
          example: reply@yourdomain.com
    Sender:
      type: object
      properties:
        id:
          type: string
          format: uuid
          description: Unique identifier.
          example: 550e8400-e29b-41d4-a716-446655440000
        name:
          type: string
          description: The sender display name.
          example: John Doe
        username:
          type: string
          description: The username part of the sender email address.
          example: john
        email:
          type: string
          format: email
          description: The full sender email address (computed from username and domain).
          example: john@yourdomain.com
        reply_to:
          type:
            - string
            - 'null'
          format: email
          description: The reply-to email address.
          example: reply@yourdomain.com
        domain:
          $ref: '#/components/schemas/DomainSummary'
          description: The domain associated with this sender (without DNS records).
        created_at:
          type: string
          format: date-time
          description: When the sender was created.
          example: '2026-03-03 10:00:00'
        updated_at:
          type: string
          format: date-time
          description: When the sender was last updated.
          example: '2026-03-03 10:00:00'
    DomainSummary:
      type: object
      properties:
        id:
          type: string
          format: uuid
          description: Unique identifier.
          example: 550e8400-e29b-41d4-a716-446655440000
        name:
          type: string
          description: The domain name.
          example: yourdomain.com
        status:
          type: string
          enum:
            - not_started
            - pending
            - verified
            - partially_verified
            - failed
            - temporary_failure
          description: The current verification status of the domain.
          example: verified
        region:
          type: string
          description: The AWS region where the domain is configured.
          enum:
            - sa-east-1
            - us-east-2
            - eu-central-1
          example: us-east-2
        open_tracking:
          type: boolean
          description: Whether open tracking is enabled.
          example: true
        click_tracking:
          type: boolean
          description: Whether click tracking is enabled.
          example: true
        tls:
          type: string
          enum:
            - opportunistic
            - enforced
          description: The TLS delivery mode.
          example: opportunistic
        sending_enabled:
          type: boolean
          description: Whether sending is enabled for this domain.
          example: true
        created_at:
          type: string
          format: date-time
          description: When the domain was created.
          example: '2026-03-03 10:00:00'
        updated_at:
          type: string
          format: date-time
          description: When the domain was last updated.
          example: '2026-03-03 10:00:00'
    ErrorResponse:
      type: object
      properties:
        name:
          type: string
          description: Error type identifier.
          example: validation_error
        message:
          type: string
          description: Human-readable error message.
          example: The from address domain is not verified.
  responses:
    Unauthorized:
      description: Unauthorized — missing or invalid API key
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
          example:
            message: Invalid API key.
    ValidationError:
      description: Validation error — invalid or missing parameters
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/ErrorResponse'
          example:
            message: The email field is required.
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: >-
        API key from your SendKit dashboard. Pass it as a Bearer token in the
        Authorization header.

````