Invoke the endpoint - Amazon SageMaker
RequestResponse

Invoke the endpoint

After the endpoint is running, use the SageMaker Runtime InvokeEndpoint API in the SageMaker Runtime service to send requests to, or invoke the endpoint. In response, the requests are handled as explainability requests by the SageMaker Clarify explainer.

Note

To invoke an endpoint, choose one of the following options:

Request

The InvokeEndpoint API has an optional parameter EnableExplanations, which is mapped to the HTTP header X-Amzn-SageMaker-Enable-Explanations. If this parameter is provided, it overrides the EnableExplanations parameter of the ClarifyExplainerConfig.

Note

The ContentType and Accept parameters of the InvokeEndpoint API are required. Supported formats include MIME type text/csv and application/jsonlines.

Use the sagemaker_runtime_client to send a request to the endpoint, as follows:

response = sagemaker_runtime_client.invoke_endpoint(
    EndpointName='name-of-your-endpoint',
    EnableExplanations='`true`',
    ContentType='text/csv',
    Accept='text/csv',
    Body='1,2,3,4',  # single record (of four numerical features)
)

For multi-model endpoints, pass an additional TargetModel parameter in the previous example request to specifies which model to target at the endpoint. The multi-model endpoint dynamically loads target models as needed. For more information about multi-model endpoints, see Host multiple models in one container behind one endpoint. See the SageMaker Clarify Online Explainability on Multi-Model Endpoint Sample Notebook for an example of how to set up and invoke multiple target models from a single endpoint.

Response

If the endpoint is created with ExplainerConfig, then a new response schema is used, This new schema is different from, and is not compatible with, an endpoint that lacks the ExplainerConfig parameter provided.

The MIME type of the response is application/json, and the response payload can be decoded from UTF-8 bytes to a JSON object. The following shows the members of this JSON object are as follows:

  • version: The version of the response schema in string format. For example, 1.0.

  • predictions: The predictions that the request makes have the following:

    • content_type: The MIME type of the predictions, referring to the ContentType of the model container response.

    • data: The predictions data string delivered as the payload of the model container response for the request.

  • label_headers: The label headers from the LabelHeaders parameter. This is provided in either the explainer configuration or the model container output.

  • explanations: The explanations provided in the request payload. If no records are explained, then this member returns the empty object {}.

    • kernel_shap: A key that refers to an array of Kernel SHAP explanations for each record in the request. If a record is not explained, the corresponding explanation is null.

The kernel_shap element has the following members:

  • feature_header: The header name of the features provided by the FeatureHeaders parameter in the explainer configuration ExplainerConfig.

  • feature_type: The feature type inferred by explainer or provided in the FeatureTypes parameter in the ExplainerConfig. This element is only available for NLP explainability problems.

  • attributions: An array of attribution objects. Text features can have multiple attribution objects, each for a unit. The attribution object has the following members:

    • attribution: A list of probability values, given for each class.

    • description: The description of the text units, available only for NLP explainability problems.

      • partial_text: The portion of the text explained by the explainer.

      • start_idx: A zero-based index to identify the array location of the beginning of the partial text fragment.