the name literally tells you: Generative Predictive Text

it's a type of path discovery algorithm that are created by grammar trees, it uses a special type of hash function that produces an approximation of the hamming distance of two nodes on the semantic graph that changes as you walk it, based on a random seed

the technology is really primitive, it's just a moderately functional natural language processing system, i prefer to call it "text mangler" because it literally eats a pile of input and then does things to it that let you pull a spaghetti string out of it that makes sense

its predecessor was the Markov Chain and back in 2004 in my customary IRC chat at the time the sysadmin of the chat deployed a markov chain bot that fed on our messages and spat back mangled versions of our text, it was quite funny because i could recognise it, and because i was one of the most prolific writers, it regurgitated a lot of expressions taht i used

that's also why if you look at the list of npubs that have muted me among them are two GPT bots :D