> ## 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.

# Send a synthetic test event

> Publishes a synthetic `sendmux.test` event to this webhook subscription. The subscription must include `"sendmux.test"` in `event_types`, and mailbox filters do not block the test delivery. Returns the generated `event_id` so you can correlate the `X-Sendmux-Event-Id` header on your endpoint.

Supply an `Idempotency-Key` header to safely retry on network errors — replays under the same key return the original `event_id` rather than publishing a second test event.



## OpenAPI

````yaml /openapi-app.json post /webhooks/{public_id}/test
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:
  /webhooks/{public_id}/test:
    post:
      tags:
        - Webhooks
      summary: Send a synthetic test event
      description: >-
        Publishes a synthetic `sendmux.test` event to this webhook subscription.
        The subscription must include `"sendmux.test"` in `event_types`, and
        mailbox filters do not block the test delivery. Returns the generated
        `event_id` so you can correlate the `X-Sendmux-Event-Id` header on your
        endpoint.


        Supply an `Idempotency-Key` header to safely retry on network errors —
        replays under the same key return the original `event_id` rather than
        publishing a second test event.
      operationId: managementTestWebhook
      parameters:
        - in: path
          name: public_id
          required: true
          schema:
            description: Webhook public ID
            type: string
        - in: header
          name: Idempotency-Key
          required: false
          schema:
            description: >-
              Client-chosen unique key to safely retry the request. Cached for
              24h per (team, endpoint, key). Different target `public_id` under
              the same key returns 409 idempotency_conflict.
            example: webhooks-test-20260424-001
            maxLength: 255
            type: string
      responses:
        '200':
          content:
            application/json:
              schema:
                allOf:
                  - $ref: '#/components/schemas/SuccessEnvelope'
                  - properties:
                      data:
                        $ref: '#/components/schemas/WebhookTestResponse'
                      meta:
                        $ref: '#/components/schemas/ResponseMeta'
                    required:
                      - data
                    type: object
                unevaluatedProperties: false
          description: Test event published
        '404':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Subscription not found
        '409':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: >-
            `Idempotency-Key` was replayed against a different webhook
            (`idempotency_conflict`) or the webhook is not subscribed to
            `sendmux.test` (`conflict`).
        '503':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ApiError'
          description: Event publish service is unavailable.
      security:
        - bearerAuth: []
components:
  schemas:
    SuccessEnvelope:
      properties:
        meta:
          additionalProperties: {}
          properties: {}
          type: object
        ok:
          enum:
            - true
          type: boolean
      required:
        - ok
        - meta
      type: object
    WebhookTestResponse:
      additionalProperties: false
      properties:
        event_id:
          description: >-
            The event_id attached to the X-Sendmux-Event-Id header of the test
            delivery.
          example: evt_clxxxxxxxxxxxxxxxxxxxxxxxxx
          type: string
      required:
        - event_id
      type: object
    ResponseMeta:
      additionalProperties: false
      properties:
        request_id:
          example: req_clxxxxxxxxxxxxxxxxxxxxxxxxx
          type: string
      required:
        - request_id
      type: object
    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
    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
  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

````