Watson: Dialogs. Are they required?

If you plan to just use intents and entities programmatically then you don’t need dialog.

You will need to create one blank dialog, with a condition of true. This is to avoid SPEL errors relating to no node found.

From a programming point of view (and ignoring conversation for a minute), if you need to take action on intents, entities, or change context variables. The recommendation is to do that in dialog. This way your code is not split across two systems, making it easier to maintain.

Probably in this phrase above, the author wants to say that you only need to create #intents and @entities for your Conversation and defining the purpose for your bot, this is true, depends on what you want to do in your bot, cause after it you can just create your dialog flow!

The Dialog section is for you create your Dialog flow, is absolutely needed when you want to create one conversation flow, e.g: one chatbot.

A workspace contains the following types of artifacts:

Intents: An intent represents the purpose of a user's input, such as a question about business locations or a bill payment. You define an intent for each type of user request you want your application to support. In the tool, the name of an intent is always prefixed with the # character. To train the workspace to recognize your intents, you supply lots of examples of user input and indicate which intents they map to.

Entities; An entity represents a term or object that is relevant to your intents and that provides a specific context for an intent. For example, an entity might represent a city where the user wants to find a business location, or the amount of a bill payment. In the tool, the name of an entity is always prefixed with the @ character. To train the workspace to recognize your entities, you list the possible values for each entity and synonyms that users might enter.

Dialog: A dialog is a branching conversation flow that defines how your application responds when it recognizes the defined intents and entities. You use the dialog builder in the tool to create conversations with users, providing responses based on the intents and entities that you recognize in their input.

EDIT:

Likes @Simon O'Doherty said, if your purpose is to just use the Intents and Entities programmatically, then you don't need the Dialog. His answer is complete.

• See the documentation for Building a Dialog.

You need Dialog portion of Watson Conversation service if you want to respond to the user queries.

The Intents and entities are the understanding piece, and the Dialog portion is the response side of the conversation.