To be more specific, understand why the client wants to build a chatbot and what the customer wants their chatbot to do. Finding answers to this query will guide the designer to create conversations aimed at meeting end goals. When the designer knows why the chatbot is being built, they are better placed to design the conversation with the chatbot.
For example, ecommerce companies will likely want a chatbot that can display products, handle shipping questions, but a healthcare chatbot would look very different. Also, while most chatbot software is continually upping the AI-ante, a company called Landbot is taking a different approach, stripping away the complexity to help create better customer conversations.
Clare.AI is a frontend assistant that provides modern online banking services. This virtual assistant combines machine learning algorithms with natural language processing. The Clare.AI algorithm is trained to respond to customer service FAQs, arrange appointments, conduct internal inquiries for IT and HR, and help customers control their finances via their favorite messaging apps (WhatsApp, Facebook, WeChat, etc.). It can even draw a chart showing customers how they’ve spent their money.
Facebook Messenger chat bots are a way to communicate with the companies and services that you use directly through Messenger. The goal of chat bots is to minimize the time you would spend waiting on hold or sifting through automated phone menus. By using keywords and short phrases, you can get information and perform tasks all through the Messenger app. For example, you could use bots to purchase clothing, or check the weather by asking the bot questions. Bot selection is limited, but more are being added all the time. You can also interact with bots using the Facebook website.

Spot is a chatbot developed by Criminal Psychologist Julia Shaw at the University College London. Using memory science and AI, Spot doesn’t just allow users to report workplace harassment and bullying, but is capable of asking personalized, open-ended questions to help you recall details about events that made you feel uncomfortable. The application helps users process what happened, to understand whether or not they experienced harassment or discrimination and offers advice on how they can take matters further.
It won’t be an easy march though once we get to the nitty-gritty details. For example, I heard through the grapevine that when Starbucks looked at the voice data they collected from customer orders, they found that there are a few millions unique ways to order. (For those in the field, I’m talking about unique user utterances.) This is to be expected given the wild combinations of latte vs mocha, dairy vs soy, grande vs trenta, extra-hot vs iced, room vs no-room, for here vs to-go, snack variety, spoken accent diversity, etc. The AI practitioner will soon curse all these dimensions before taking a deep learning breath and getting to work. I feel though that given practically unlimited data, deep learning is now good enough to overcome this problem, and it is only a matter of couple of years until we see these TODA solutions deployed. One technique to watch is Generative Adversarial Nets (GAN). Roughly speaking, GAN engages itself in an iterative game of counterfeiting real stuffs, getting caught by the police neural network, improving counterfeiting skill, and rinse-and-repeating until it can pass as your Starbucks’ order-taking person, given enough data and iterations.
Chatfuel is a platform that lets you build your own Chatbot for Messenger (and Telegram) for free. The only limit is if you pass more than 100,000 conversations per month, but for most businesses that won't be an issue. No understanding of code is required and it has a simple drag-and-drop interface. Think Wix/Squarespace for bots (side note: I have zero affiliation with Chatfuel).

An Internet bot, also known as a web robot, WWW robot or simply bot, is a software application that runs automated tasks (scripts) over the Internet.[1] Typically, bots perform tasks that are both simple and structurally repetitive, at a much higher rate than would be possible for a human alone. The largest use of bots is in web spidering (web crawler), in which an automated script fetches, analyzes and files information from web servers at many times the speed of a human. More than half of all web traffic is made up of bots.[2]

There is no one right answer to this question, as the best solution will depend upon the specifics of your scenario and how the user would reasonably expect the bot to respond. However, as your conversation complexity increases dialogs become harder to manage. For complex branchings situations, it may be easier to create your own flow of control logic to keep track of your user's conversation.
Through Amazon’s developer platform for the Echo (called Alexa Skills), developers can develop “skills” for Alexa which enable her to carry out new types of tasks. Examples of skills include playing music from your Spotify library, adding events to your Google Calendar, or querying your credit card balance with Capital One — you can even ask Alexa to “open Dominoes and place my Easy Order” and have pizza delivered without even picking up your smartphone. Now that’s conversational commerce in action.
In 1950, Alan Turing's famous article "Computing Machinery and Intelligence" was published,[7] which proposed what is now called the Turing test as a criterion of intelligence. This criterion depends on the ability of a computer program to impersonate a human in a real-time written conversation with a human judge, sufficiently well that the judge is unable to distinguish reliably—on the basis of the conversational content alone—between the program and a real human. The notoriety of Turing's proposed test stimulated great interest in Joseph Weizenbaum's program ELIZA, published in 1966, which seemed to be able to fool users into believing that they were conversing with a real human. However Weizenbaum himself did not claim that ELIZA was genuinely intelligent, and the introduction to his paper presented it more as a debunking exercise:
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