# Get OpenAPI definition


```
GET 
https://api.apify.com/v2/acts/:actorId/builds/:buildId/openapi.json
```


Get the OpenAPI definition for Actor builds. Two similar endpoints are available:

* [First endpoint](https://pr-2251.preview.docs.apify.com/api/v2/act-openapi-json-get.md): Requires both `actorId` and `buildId`. Use `default` as the `buildId` to get the OpenAPI schema for the default Actor build.

* [Second endpoint](https://pr-2251.preview.docs.apify.com/api/v2/actor-build-openapi-json-get.md): Requires only `buildId`.

Get the OpenAPI definition for a specific Actor build.

To fetch the default Actor build, simply pass `default` as the `buildId`. Authentication is based on the build's unique ID. No authentication token is required.

note

You can also use the [/api/v2/actor-build-openapi-json-get](https://pr-2251.preview.docs.apify.com/api/v2/actor-build-openapi-json-get.md) endpoint to get the OpenAPI definition for a build.

## Request

### Path Parameters

* **actorId** string required

  Actor ID or a tilde-separated owner's username and Actor name.

  **Example:** `janedoe~my-actor`

  **buildId** string required

  ID of the build you want to get, found in the build's `Info` tab. Pass `default` for default Actor build.

  **Example:** `soSkq9ekdmfOslopH`

<!-- -->

### Status 200

The OpenAPI specification document for the Actor build.

**Response Headers**




```
{}
```


**Schema**

* **object** object

  A standard OpenAPI 3.x JSON document.

### Status 400

Bad request - invalid input parameters or request body.


```
{
  "error": {
    "type": "invalid-input",
    "message": "Invalid input: The request body contains invalid data."
  }
}
```


**Schema**

* **error** object required

  * **type** string required\
    **Example:** `run-failed`
  * **message** string required\
    **Example:** `Actor run did not succeed (run ID: 55uatRrZib4xbZs, status: FAILED)`