Language Understanding (LUIS) REST API reference - Azure Cognitive Services

This article demonstrates how to call a REST API endpoint for Language Understanding service (LUIS), a service in Azure Cognitive Services suite. LUIS is a cloud-based conversational AI service that applies custom machine-learning intelligence to a user's conversational, natural language text to predict overall meaning, and pull out relevant, detailed information.

Call the LUIS endpoint

  1. Start by creating an Azure Cognitive Services resource, and within that specifically a LUIS resource. For instructions, see Create a Cognitive Services resource using the portal.

  2. From the Azure Portal, copy the key and endpoint required to make the call. For instructions, see Get the keys for your resource.

  3. From the left navigation on this article, expand the node for the version of the API you want to work on, and then select the operation that you want to perform (e.g., Train Version). On the right pane, select Try It.

  4. In the REST API Try It pane, perform the following steps:

    1. In the Endpoint text box, enter the resource endpoint that you copied from the Azure portal.
    2. In the Ocp-Apim-Subscription-Key text box, enter the key that you copied from the Azure portal. If the call requires any more headers, add those with the appropriate values as well.
    3. Provide other parameters, headers, and message payload (body) as required for the operation.
    4. Select Run.
  5. You will see the relevant response with an appropriate response code.


Visit the Cognitive Services REST API Sample Github repo for various samples on working with Cognitive Services using REST.

See also