# `mockServer`

Configure a mock server in your Redocly-powered API documentation.
The mock server allows users to:

- Send requests to the Operations in your API description from Replay, cURL, or any other API client.
- Receive a sample response using information from the API description and input data.

By default, the mock server is enabled for each [API description](https://redocly.com/docs/resources/learning-openapi) in your project.
The path is configured as `/_mock/<path-to-description>/`.
For example, `/_mock/openapi/redocly-museum/`.

## Options

| Option | Type | Description |
| --- | --- | --- |
| off | boolean | Turn off ("disable") the mock server. Default: `false`. |
| strictExamples | boolean | If `true`, example responses are returned unmodified, exactly how they're described in the API description.  If `false`, the mock server substitutes fields in the response payload with values provided in the request.  Default: `false`. |
| errorIfForcedExampleNotFound | boolean | Controls the response behavior of the mock server when a [forced example](/docs/realm/content/api-docs/configure-mock-server#understand-strict-examples) is not found.  If `true`, the mock server returns an error.  If `false`, the mock server falls back to any other example defined for that operation.  Default: `false`. |
| position | string | Controls the position of the mock server in the servers dropdown in Redocly Replay. Possible values: `first`, `last`, `replace`, `off`. Default: `first`. |
| description | string | Set the description of the mock server in the servers dropdown in Redocly Replay. Default: `Mock server`. |

## Examples

This example configures the mock server in the following ways:

- Example response payloads don't substitute values from the request.
- Only the mock server is available on Replay's server list.
- The mock server is labeled as "Development server".

```yaml
mockServer:
  strictExamples: true
  position: 'replace'
  description: 'Development Server'
```

## Resources

- **[Replay API explorer](https://redocly.com/docs/end-user/test-apis-replay)** - Learn about the interactive API testing features and capabilities used in API reference documentation
- **[Test APIs using CLI](https://redocly.com/docs/end-user/test-apis-cli)** - Learn about the interactive API testing features and capabilities used in API reference documentation
- **[Configure the mock server](/docs/realm/content/api-docs/configure-mock-server)** - Learn to modify mock server behavior and appearance for enhanced API testing and development
- **[Add OpenAPI descriptions](/docs/realm/content/api-docs/add-openapi-docs)** - Add OpenAPI descriptions to enable mock server functionality on the corresponding API reference documentation