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

# Get a mailbox submission

> Returns one send submission for the authenticated mailbox. Responses include a weak `ETag` header.



## OpenAPI

````yaml /openapi-app.json get /mailbox/submissions/{submission_id}
openapi: 3.1.0
info:
  description: Programmatic access to your Sendmux email infrastructure.
  title: Sendmux API
  version: 1.0.0
servers:
  - description: API v1
    url: https://app.sendmux.ai/api/v1
security:
  - bearerAuth: []
paths:
  /mailbox/submissions/{submission_id}:
    get:
      tags:
        - Mailbox API
      summary: Get a mailbox submission
      description: >-
        Returns one send submission for the authenticated mailbox. Responses
        include a weak `ETag` header.
      operationId: mailboxGetSubmission
      parameters:
        - in: path
          name: submission_id
          required: true
          schema:
            type: string
        - in: header
          name: If-None-Match
          required: false
          schema:
            type: string
        - description: >-
            Mailbox public ID to target when the credential grants access to
            more than one mailbox. Omit when the credential is scoped to exactly
            one mailbox.
          in: query
          name: mailbox_id
          required: false
          schema:
            type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/MailboxSubmissionResponse'
          description: Submission
        '304':
          description: Not modified
        '404':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Submission not found
      security:
        - bearerAuth: []
components:
  schemas:
    MailboxSubmissionResponse:
      allOf:
        - $ref: '#/components/schemas/SuccessEnvelope'
        - properties:
            data:
              $ref: '#/components/schemas/MailboxSubmission'
            meta:
              $ref: '#/components/schemas/ResponseMeta'
          required:
            - data
          type: object
      unevaluatedProperties: false
    ApiError:
      additionalProperties: false
      properties:
        error:
          additionalProperties: false
          properties:
            code:
              description: Machine-readable error code
              enum:
                - invalid_parameter
                - missing_parameter
                - authentication_required
                - insufficient_permissions
                - not_found
                - conflict
                - limit_exceeded
                - idempotency_conflict
                - payload_too_large
                - validation_error
                - rate_limit_exceeded
                - service_unavailable
                - internal_error
              example: invalid_parameter
              type: string
            doc_url:
              description: Link to relevant documentation
              type: string
            errors:
              description: >-
                Accumulated per-field issues for validation errors. Only present
                on 400/422 responses.
              items:
                $ref: '#/components/schemas/ApiErrorDetail'
              type: array
            message:
              description: Human-readable error description
              type: string
            param:
              description: The parameter that caused the error
              type: string
            retryable:
              description: >-
                Whether the caller may safely retry this request. 4xx are
                typically false (except 429); 5xx are typically true.
              example: false
              type: boolean
          required:
            - code
            - message
            - retryable
          type: object
        meta:
          additionalProperties: false
          properties:
            request_id:
              example: req_clxxxxxxxxxxxxxxxxxxxxxxxxx
              type: string
          required:
            - request_id
          type: object
        ok:
          enum:
            - false
          type: boolean
      required:
        - ok
        - error
        - meta
      type: object
    SuccessEnvelope:
      properties:
        meta:
          additionalProperties: {}
          properties: {}
          type: object
        ok:
          enum:
            - true
          type: boolean
      required:
        - ok
        - meta
      type: object
    MailboxSubmission:
      additionalProperties: false
      properties:
        delivery_status:
          items:
            $ref: '#/components/schemas/MailboxSubmissionDeliveryStatus'
          type: array
        dsn_blob_ids:
          items:
            type: string
          type: array
        email_id:
          type:
            - string
            - 'null'
        envelope:
          $ref: '#/components/schemas/MailboxSubmissionEnvelope'
        id:
          description: Submission ID
          type: string
        identity_id:
          type:
            - string
            - 'null'
        mdn_blob_ids:
          items:
            type: string
          type: array
        send_at:
          type:
            - string
            - 'null'
        thread_id:
          type:
            - string
            - 'null'
        undo_status:
          type:
            - string
            - 'null'
      required:
        - id
        - identity_id
        - email_id
        - thread_id
        - send_at
        - undo_status
        - envelope
        - delivery_status
        - dsn_blob_ids
        - mdn_blob_ids
      type: object
    ResponseMeta:
      additionalProperties: false
      properties:
        request_id:
          example: req_clxxxxxxxxxxxxxxxxxxxxxxxxx
          type: string
      required:
        - request_id
      type: object
    ApiErrorDetail:
      additionalProperties: false
      properties:
        code:
          description: >-
            Machine-readable issue code from the validator (e.g. zod issue
            code).
          example: invalid_string
          type: string
        field:
          description: Dot-path of the offending request field.
          example: recipient.email
          type: string
        message:
          description: Human-readable issue description.
          type: string
      required:
        - field
        - code
        - message
      type: object
    MailboxSubmissionDeliveryStatus:
      additionalProperties: false
      properties:
        delivered:
          type:
            - string
            - 'null'
        displayed:
          type:
            - string
            - 'null'
        email:
          format: email
          type: string
        smtp_reply:
          type:
            - string
            - 'null'
      required:
        - email
        - smtp_reply
        - delivered
        - displayed
      type: object
    MailboxSubmissionEnvelope:
      additionalProperties: false
      properties:
        mail_from:
          $ref: '#/components/schemas/MailboxSubmissionEnvelopeAddress'
        rcpt_to:
          items:
            allOf:
              - $ref: '#/components/schemas/MailboxSubmissionEnvelopeAddress'
              - type: object
          type: array
      required:
        - mail_from
        - rcpt_to
      type:
        - object
        - 'null'
    MailboxSubmissionEnvelopeAddress:
      additionalProperties: false
      properties:
        email:
          format: email
          type: string
        parameters:
          additionalProperties:
            type:
              - string
              - 'null'
          type:
            - object
            - 'null'
      required:
        - email
        - parameters
      type:
        - object
        - 'null'
  securitySchemes:
    bearerAuth:
      bearerFormat: API Key
      description: >-
        Sendmux API key. Use a root API key for Management API routes, or a
        mailbox credential for Mailbox API routes. Obtain keys from the
        dashboard under API Keys.
      scheme: bearer
      type: http

````