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

# Send a test webhook

> Send one signed `webhook.test` event to `callback_url` now, to check that your endpoint is reachable and verifies signatures, without running a job. The URL goes through the same checks as a job's `callback_url` (400 names the rule it broke), and the event is signed with the project's secret like any other. One attempt, no retries: the answer says whether your endpoint took it (`delivered`, a 2xx), its `status_code`, or what went wrong. At most 10 a minute per project (429).

See the [Webhooks guide](https://docs.opper.ai/build/multimodal/webhooks.md) for setup, signature verification and retries.


## OpenAPI

````yaml post /v3/webhooks/test
openapi: 3.1.0
info:
  description: Schema-driven generative API that orchestrates LLM-powered workflows.
  title: Task API
  version: 3.0.0
servers:
  - description: Production
    url: https://api.opper.ai
  - description: Local development
    url: http://localhost:8080
security:
  - BearerAuth: []
tags:
  - description: OpenAI-compatible chat completions
    name: Chat
  - description: OpenAI Responses API compatible endpoint
    name: Responses
  - description: Google-compatible interactions endpoint
    name: Interactions
  - description: Model registry and capabilities
    name: Models
  - description: Synchronous image generation
    name: Images
  - description: Text-to-speech and speech-to-text
    name: Audio
  - description: Asynchronous video generation
    name: Videos
  - description: Realtime WebSocket sessions and their ephemeral tickets
    name: Realtime
  - description: Many requests on a provider's batch API at the batch price
    name: Batches
  - description: Reusable file storage for media inputs and generated outputs
    name: Files
  - description: Async generation status and downloads
    name: Artifacts
  - description: >-
      Signed completion webhooks for async jobs, and the project secret that
      signs them
    name: Webhooks
  - description: OpenAI-compatible embeddings
    name: Embeddings
  - description: Recorded HTTP request/response generations
    name: Generations
  - description: System health and status
    name: System
  - description: Roundtable endpoint — fan out a query to multiple LLMs and combine results
    name: Roundtable
  - description: Web search, fetch, and other utility tools
    name: Tools
  - description: Caller identity, credits, and usage
    name: Account
  - description: >-
      Programmatic project and API-key management. Authenticates with an
      `op-mak-…` management token; available on the control_plane and enterprise
      plans.
    name: Management
paths:
  /v3/webhooks/test:
    post:
      tags:
        - Webhooks
      summary: Send a test webhook
      description: >-
        Send one signed `webhook.test` event to `callback_url` now, to check
        that your endpoint is reachable and verifies signatures, without running
        a job. The URL goes through the same checks as a job's `callback_url`
        (400 names the rule it broke), and the event is signed with the
        project's secret like any other. One attempt, no retries: the answer
        says whether your endpoint took it (`delivered`, a 2xx), its
        `status_code`, or what went wrong. At most 10 a minute per project
        (429).
      operationId: testWebhook
      requestBody:
        content:
          application/json:
            schema:
              properties:
                callback_url:
                  description: The https URL to POST the test event to.
                  type: string
              required:
                - callback_url
              type: object
        required: true
      responses:
        '200':
          content:
            application/json:
              schema:
                properties:
                  data:
                    properties:
                      delivered:
                        description: Your endpoint answered 2xx.
                        type: boolean
                      duration_ms:
                        type: integer
                      error:
                        description: What went wrong, when not delivered.
                        type: string
                      status_code:
                        description: >-
                          What your endpoint answered; absent when no answer
                          came.
                        type: integer
                      webhook_id:
                        description: The webhook-id header the event carried.
                        type: string
                    required:
                      - delivered
                      - webhook_id
                      - duration_ms
                    type: object
                  meta:
                    type: object
                type: object
          description: Successful response
        '400':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
          description: Bad request
        '401':
          description: Unauthorized - missing or invalid API key
        '500':
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
          description: Internal server error
components:
  schemas:
    ErrorResponse:
      properties:
        error:
          properties:
            code:
              type: string
            details:
              description: Any value
            message:
              type: string
          required:
            - code
            - message
          type: object
        meta:
          type: object
      required:
        - error
      type: object
  securitySchemes:
    BearerAuth:
      bearerFormat: API Key
      description: API key authentication. Pass your API key as a Bearer token.
      scheme: bearer
      type: http

````

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