Is it possible to embed the AI used in evie cleverbot into a game? For example GTA5 or Sims, to enabe conversations and mood that is if you type something and the game characters will react to what you said and respond back. Is it possible to do this?
Is it possible?
Sure. Natural language processing AI is a very well-researched topic. You can find lots of descriptions of the algorithms used. It's also a very popular topic for computer science dissertations, so when you don't feel like diving into this topic yourself you can likely hire someone right out of university for cheap who is familiar with the topic. You can also contact one of the companies which work in that area and license their technology.
Is it feasible?
A natural language AI must be trained to be able to create the illusion of conversations about certain topics. Most of the well-known chatbots like Cleverbot are crowdsourced. The developers just put the AI online and have it learn by having millions of internet users interact with them. The AI copies the users and adopts their manners of speech. That can backfire colossally like the Microsoft Twitter AI which the Internet turned into a nazi.
When you want to train a chat AI, you need to train it in the context where you want it to behave. So when you want an AI to emulate the personality of a gang member or knight or space pirate in your game, then you need to train them by interacting with them in-character and reply like you would expect them to. A lot! This is a very long and tedious process you can not easily crowdsource or automatize.
Is it user-friendly?
Back in the 80s, text parsers were very popular. Many adventure games were just text and the player was typing what they wanted to do ("go west", "take broom", "talk to bob", "give broom to bob"...). But such interfaces were soon replaced by point-and-click interfaces. Why? Because they were just annoying to use. Ask yourself what's more convenient to the player: Typing out the sentence "I feel honored to take on this great quest and rescue the princess from the evil wizard" or to just click on it.
With today's voice recognition technology you could maybe replace that by having the player speak into the microphone and parse their speech. I am not aware of any games which really tried to use this seriously beyond some little gimmicks.
But if you can make it work, would it be useful for game development?
When you design a game, NPCs usually have a certain purpose. Either mechanically (they sell the player items they need, they open doors for them) or narrative (they tell them where the next mission is, why they need to do it and make them emotionally invested). Some NPCs are just background, like the pedestrians in GTA. The player can usually only interact with them in very simple ways. But it needs to be simple to not distract the player from your actual game.
When you automatize NPC behavior with an AI, you lose control and can no longer ensure that the NPCs do what they are supposed to do when they are supposed to do it.
This can be dangerous. Imagine the player befriends GLaDOS in Portal, alienates Elizabeth in Bioshock Infinite and gets Commander Shepard in Mass Effect dishonorably discharged within the first minutes of the game. Then there would be no game to play and no story to tell anymore. Sure, you could have all of that as a failure condition resulting in instant game-over, but social interactions are just too unpredictable to estimate what conditions will break the game and what conditions won't.
A good example where too good AI can fail is Bethesda and their "Radiant AI". The developers kept experimenting with completely unscripted NPCs throughout the Elder Scrolls and 3d Fallout series. But it just wouldn't work. NPCs were killing each other over a loaf of bread, break critical quests by solving them on their own and completely ignored the player-character. In the end every game ended up using almost completely scripted NPCs and left the totally AI-controlled NPCs to the next version.