Essential insights from Hacker News discussions

Importance of context management in AI NPCs

Here's a summary of the themes expressed in the Hacker News discussion:

The Nature of Context and NPC Behavior

A central theme revolves around how AI NPCs should manage and be presented with contextual information, especially in dynamic game worlds. The discussion explores the trade-offs between feeding NPCs all world events versus only those they would realistically encounter, and the implications for player immersion.

  • On limiting context for realism: "We will probably get something more formalized , like "context occlusion", for games in the future." (k__)
  • On the original vs. changed system: "Seems like his original system (the universe broadcasts to every NPC even while they are not doing anything) could fudge that a bit and retain a feeling of ongoing background life, in some cases. While in the new system they are ready frozen… I dunno. What to do? Maybe run a simplified model and have it generate some appropriate local events for the NPCs while they are frozen (some, fewer than when they were on the receiving end of the whole universe)." (bee_rider)
  • On faking NPC activity when the player returns: "I think you can mostly fake this by waiting until the player reenters the range to generate what happened since the last time they interacted. If it's a complex simulation it won't work without more effort, but if it's flavor text like "Bob told me last week you killed the dragon, nice work!" then it can be done like 5ms after the player enters the simulation radius of the NPC." (pmichaud)
  • On player perception of NPC lives: "When two people leave the house in the morning and return home at night, does either person truly know what happened with the other person? Almost every interaction you have with other people is just “filling in” reality (reality is sparse, as far as you are concerned)." (ivape)

Practical Challenges and Implementations of Context Engineering

The discussion highlights the current technical limitations and potential future approaches for implementing "context engineering," particularly concerning performance and the ability of LLMs to retain and utilize vast amounts of context.

  • On performance degradation with context: "In my local ai (mistral-nemo) around 10 thousand tokens of context decreases my token gen speed from 70t/s to 20 t/s . And the LLM starts ignoring the context after a while." (123yawaworht456)
  • On the viability of local vs. cloud models: "as much as it pains me to say this, only cloud models are somewhat viable for this. AI-powered NPCs are my dream too, and after many attempts with countless local and cloud models, I've given up for now. locals are retarded and incurably sloppy, clouds can be tard-wrangled into producing somewhat decent prose, but they are prohibitively expensive." (123yawaworht456)
  • On background simulation in existing games: "More primitive, but this is technically how AI in Bethesda games work, has this background simulation for NPCs going on when out of sight. Think it's mainly focused on movement patterns though." (yesco)
  • On parallelization and off-loading: "Parallelization and off-load to beefy computers. Run a more complete simulation, stream the results back to the player, and define boundaries where things become sequential." (randysalami)
  • On action masking in agent design: "Also observation and action masking is being explored as a core part of agent design. Definitely a skill and something that needs to be thoughtful for it to work but see where action masking is being applied in PettingZoo environments using Langchain." (randysalami)

The Core Nature of LLM Behavior and Persona Management

A significant portion of the conversation delves into the fundamental limitations of LLMs when it comes to maintaining specific personas or character constraints, suggesting that the issue goes beyond simple context management.

  • On LLMs knowing too much outside character context: "The problem with AI NPCs is actually not strictly a context problem and cannot be fixed with prompt engineering or RAG, because the LLM knows a vast amount of stuff outside of the context you feed it. No matter how you tell it how to roleplay or how many instructions you give it or don't give it, there is always the problem that you can ask it to write a front end app in JS for you and it will. Or ask it about the theory of relativity or anything else that the AI is capable of conversing about but the character would not be. It is trivially easy to jailbreak out of fictional personas." (empath75)
  • On AI inference as role-playing: "I think people forget that all AI inference is role playing to some extent. It pretends to be a chatbot, or a programmer, or whatever. There is no real difference between that and telling it to pretend to be a wizard." (empath75)

The Role of Writing and Design in NPC Depth

The discussion touches on how traditional game design principles, like good writing and thoughtful characterization, can still be effective in simulating depth for NPCs, even with limitations in AI.

  • On achieving depth through writing: "You can effectively accomplish something like this already simply through good writing and programming, accounting for these gaps as part of an NPC's characterization. It's a cool way to play with player expectations, and one of the core bases behind Toby Fox's games." (nluken)

Analogy to Software Stability and Optimization

One user draws an analogy between the challenges of context management in AI with the historical need for rebooting operating systems, suggesting that current approaches might be overly focused on workarounds rather than fundamental solutions.

  • On "workflow optimization for reboots": "My OS gets slower and buggy if I don't reboot. So I'll try to convince my users to reboot often and optimize their workflows for rebootability. Feels like trying to solve a problem that shouldn't exist in the first place. Once an OS that doesn't require reboots appear, this concept will look silly and everyone that optimized their workflows for reboots will look like dorks." (alganet)