Build a QnA Bot

For customer support scenarios, it’s common to create a bot that can interpret and answer frequently asked questions through a website chat window, email, or voice interface. Underlying the bot interface is a knowledge base of questions and appropriate answers that the bot can search for suitable responses.

Create a QnA Maker Knowledge Base

The QnA Maker service is a cognitive service in Azure that enables you to quickly create a knowledge base, either by entering question and answer pairs or from an existing document or web page. It can then use some built-in natural language processing capabilities to interpret questions and find appropriate answers.

  1. Open the QnA Maker portal at https://qnamaker.ai. Sign in using the Microsoft account associated with your Azure subscription.
  2. In the QnA Maker portal, select Create a knowledge base.
  3. If you haven’t previously created a QnA service resource, select the Preview option and then click Create a QnA service. The Azure portal will be opened in another tab so you can create a QnA Maker service in your subscription.
  4. In the Select additional features page, select Custom question answering. Then click Continue to create your resource.
  5. Enter the following settings, and then select Review and create:
    • Subscription: Your Azure subscription
    • Resource group: Select an existing resource group or create a new one
    • Name: A unique name for your QnA resource
    • Pricing tier: Standard S
    • Azure Search location: Any available location
    • Azure Search pricing tier: Free F
    • Notices. If any notices are displayed, select the appropriate checkboxes to state you have read them.

Note: If you have already provisioned a free-tier Azure Cognitive Search resources, your quota may not allow you to create another one. In which case, select a tier other than F.

  1. Click Create and wait for the deployment of the Text Analytics Service that will support your QnA knowledge base.
  2. Return to the QnA Maker portal tab, and in the Step 2 section, click Refresh to refresh the list of available QnA service resources.
  3. Connect your QnA service to your KB by selecting the following options:
    • Microsoft Azure Directory ID: The Azure directory ID for your subscription
    • Azure subscription name: Your Azure subscription
    • Azure QnA service: The QnA service resource you created in the previous step
    • Language: English

    Tip: If a message stating that the role does not have permission to perform the action is displayed, refresh the browser page for the QnA Maker portal.

  4. In the Step 3 section, enter the name Margie’s Travel KB.
  5. In the Step 4 section, in the URL box, type https://github.com/GraemeMalcolm/ai-stuff/raw/main/data/qna/margies_faq.docx and click + Add URL. Then under Chit-chat, select Professional.
  6. In the Step 5 section, click Create your KB.
  7. Wait for a minute or so while your Knowledge base is created. Then review the questions and answers that have been imported from the FAQ document and the professional chit-chat pre-defined responses.

Edit the Knowledge Base

Your knowledge base is based on the details in the FAQ document and some pre-defined responses. You can add custom question-and-answer pairs to supplement these.

  1. Click + Add QnA pair.
  2. In the Question box, type Hello. Then click + Add alternative phrasing and type Hi.
  3. In the Answer box, type Hello.

Train and Test the Knowledge Base

Now that you have a knowledge base, you can test it in the QnA Maker portal.

  1. At the top right of the page, click Save and train to train your knowledge base. You may need to change the size of your window to see the button.
  2. After training has completed, click ← Test to open the test pane.
  3. In the test pane, at the bottom enter the message Hi. The response Hello should be returned.

  4. In the test pane, at the bottom enter the message I want to book a flight. An appropriate response from the FAQ should be returned.

    Note that the response includes a short answer as well as a more verbose answer passage - the answer passage shows the full text in the FAQ document for the closest matched question, while the short answer is intelligently extracted from the passage. You can control whether the short answer from the response by using the Display short answer checkbox at the top of the test pane.

  5. Try another question, such as How can I cancel a reservation?
  6. When you’re done testing the knowledge base, click → Test to close the test pane.

Publish and use the Knowledge Base

The knowledge base provides a back-end service that client applications can use to answer questions through some sort of user interface. Commonly, these client applications are bots. To make the knowledge base available to a bot, you must publish it as a service that can be accessed over HTTP. You can then use the Azure Bot Service to create and host a bot that uses the knowledge base to answer user questions.

  1. At the top of the QnA Make page, click Publish. Then in the Margies Travel KB page, click Publish.
  2. After the service has been deployed, click Create Bot. This opens the Azure portal in a new browser tab so you can create a Web App Bot in your Azure subscription.
  3. In the Azure portal, create a Web App Bot with the following settings (most of these will be pre-populated for you):
    • Bot handle: A unique name for your bot
    • Subscription: Your Azure subscription
    • Resource group: The resource group containing your QnA Maker resource
    • Location: The same location as your QnA Maker service.
    • Pricing tier: Free F0
    • App name: Same as the Bot handle with .azurewebsites.net appended automatically
    • SDK language: Choose either C# or Node.js
    • QnA Auth Key: This should automatically be set to the authentication key for your QnA knowledge base
    • App service plan/location: This should be set automatically to a suitable plan and location. If not, create a new plan.
    • Application Insights: Off
    • Microsoft App ID and password: Auto create App ID and password.
  4. Wait for your bot to be created (the notification icon at the top right, which looks like a bell, will be animated while you wait). Then in the notification that deployment has completed, click Go to resource (or alternatively, on the home page, click Resource groups, open the resource group where you created the web app bot, and click it.)
  5. In the left-hand pane of your bot look for Settings, click on Test in Web Chat, and wait until the bot displays the message Hello and welcome! (it may take a few seconds to initialize).
  6. Use the test chat interface to ensure your bot answers questions from your knowledge base as expected. For example, try submitting I need to cancel my hotel.