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

# Send an email message

> Sends a reply email to a prospect. The reply is sent in the context of an existing email thread. Rate limited to 10 requests per minute.



## OpenAPI

````yaml POST /inbox/email/messages/send
openapi: 3.1.0
info:
  title: Alta API
  description: >-
    The Alta public API allows you to programmatically access and manage your
    campaigns, prospects, companies, persons, email messages, LinkedIn messages,
    calls, reps, tags, and trigger assistant calls.
  version: 1.0.0
servers:
  - url: https://api.altahq.com/v1
    description: Production
security:
  - bearerAuth: []
paths:
  /inbox/email/messages/send:
    post:
      tags:
        - Inbox
      summary: Send an email message
      description: >-
        Sends a reply email to a prospect. The reply is sent in the context of
        an existing email thread. Rate limited to 10 requests per minute.
      operationId: sendEmailMessage
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/SendEmailMessageRequest'
      responses:
        '200':
          description: Email sent successfully
          content:
            application/json:
              schema:
                type: object
                required:
                  - messageId
                properties:
                  messageId:
                    type: string
                    format: uuid
                    description: The ID of the sent email message.
        '400':
          $ref: '#/components/responses/BadRequest'
        '401':
          $ref: '#/components/responses/Unauthorized'
        '429':
          $ref: '#/components/responses/RateLimited'
components:
  schemas:
    SendEmailMessageRequest:
      type: object
      required:
        - prospectId
        - emailMessageIdToReplyTo
        - body
      properties:
        prospectId:
          type: string
          format: uuid
          description: The UUID of the prospect to send the email to.
        emailMessageIdToReplyTo:
          type: string
          format: uuid
          description: >-
            The UUID of the email message to reply to. The reply is sent in the
            same thread.
        body:
          type: string
          minLength: 1
          description: The email body content.
        recipients:
          type: object
          description: >-
            Override the default recipients. If omitted, replies to the original
            sender.
          required:
            - to
          properties:
            to:
              type: array
              items:
                $ref: '#/components/schemas/EmailMessageContactInfo'
              description: Primary recipients.
            cc:
              type: array
              items:
                $ref: '#/components/schemas/EmailMessageContactInfo'
              description: CC recipients.
            bcc:
              type: array
              items:
                $ref: '#/components/schemas/EmailMessageContactInfo'
              description: BCC recipients.
    EmailMessageContactInfo:
      type: object
      required:
        - name
        - email
      properties:
        name:
          type: string
          description: Display name of the contact.
        email:
          type: string
          format: email
          description: Email address of the contact.
    Error:
      type: object
      required:
        - error
        - message
      properties:
        error:
          type: string
          description: Error type.
        message:
          type: string
          description: Human-readable error message.
  responses:
    BadRequest:
      description: The request body is invalid.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error: ValidationError
            message: Invalid request body
    Unauthorized:
      description: Authentication failed - invalid or missing API token.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error: Unauthorized
            message: Invalid API token
    RateLimited:
      description: >-
        Too many requests - you've exceeded the rate limit of 100 requests per
        minute.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Error'
          example:
            error: TooManyRequests
            message: Rate limit exceeded. Please retry after 60 seconds.
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: >-
        API token authentication. Generate a token from the Alta dashboard and
        pass it as a Bearer token in the Authorization header.

````