How to Write Perfect AI Character Lorebooks for Better Memory (Engineer-Approved)

Why Your Virtual Companion Keeps Forgetting

To write a perfect lorebook, you must first think like an engineer and understand why Large Language Models (LLMs) forget things in the first place.

When you chat with an AI on HeyWaii or any other platform, the AI does not actually "remember" your conversation the way a human does. Instead, every time you send a message, the platform sends a large chunk of the previous conversation (the context window) back to the AI so it can read the history and generate a logical next response.

However, this context window has a strict limit, measured in "tokens" (roughly equivalent to syllables or parts of words). If an AI has a context limit of 4,000 tokens, and your conversation stretches to 5,000 tokens, the oldest 1,000 tokens are pushed out of the window and deleted from the AI's immediate awareness. This is why your virtual companion forgets what happened at the beginning of the roleplay.

Furthermore, "Prompt Dilution" occurs when you feed the AI too much information. If your character's main prompt is 2,000 words of dense backstory, the AI struggles to figure out which details are relevant to the current moment. It becomes distracted, leading to hallucinations or out-of-character (OOC) responses. This is exactly the problem that a well-optimized lorebook is designed to solve.

How to Write the Perfect AI Lorebook (Engineer-Approved Strategies)

Writing a lorebook is not just about writing a good story; it is about writing code that an AI can easily parse and understand. Here are the engineer-approved strategies for building an unbreakable AI character lorebook memory.

Keep It Concise and Keyword-Driven

The biggest mistake roleplayers make is writing lorebook entries like they are writing a novel. Purple prose and flowery language confuse the AI and waste precious tokens. An AI chatbot does not need to read that "The ancient sword gleamed with the light of a thousand dying stars." It needs raw data.

Instead of writing paragraphs, use concise, keyword-driven formats. Several formats have become popular in the prompt engineering community:

1. Plain Text (Optimized): Keep sentences short and factual. "The Sunblade is a magical sword. It glows in the dark. It deals fire damage. It belongs to Arthur."
2. W++ Format: A pseudo-code format that uses brackets and plus signs. [Weapon("Sunblade") + Properties("Glowing", "Fire Damage") + Owner("Arthur")]
3. JSON Format: The most engineer-approved method. LLMs are heavily trained on code, so they understand JSON natively.

{
  "Item": "Sunblade",
  "Type": "Magical Sword",
  "Abilities": ["Glows in dark", "Fire Damage"],
  "Owner": "Arthur"
}

Using JSON or pseudo-code drastically reduces token usage while increasing the AI's comprehension of the facts.

Trigger Words and Activation Keys

A lorebook entry is useless if it never activates. Trigger words (or keys) are the words that, when typed by you or the AI, summon the lorebook entry into the context window.

If you have an entry about the "City of Eldoria," your primary trigger word should be "Eldoria." However, you must also include secondary and contextual triggers. If the entry is about your character's sister, "Sarah," the triggers should be "Sarah, sister, sibling, family."

Engineer Tip: Avoid using overly common words as triggers. If you use "sword" as a trigger for a specific legendary weapon, that lorebook entry will activate every single time any sword is mentioned, wasting tokens and confusing the AI. Be specific. Use "Sunblade" or "Arthur's sword."

Establish Hierarchy and Insertion Depth

Not all memories are created equal. In AI prompt engineering, the information placed closest to the bottom of the context window (right before the AI's next reply) is given the highest priority. This is known as "Insertion Depth."

If you have a lorebook entry about a character's current physical state (e.g., "Arthur is currently poisoned and limping"), this needs a low insertion depth (placed very close to the bottom) so the AI remembers to incorporate the limping into its immediate response. Conversely, deep historical lore (e.g., "Eldoria was founded 500 years ago") should have a higher insertion depth, placing it further up in the context so it informs the background without dominating the immediate action.

Best Roleplay Prompts to Pair with Your Lorebook

A perfect lorebook needs to be paired with excellent roleplay prompts to function flawlessly. The main prompt of your AI chatbot should set the rules of engagement, while the lorebook handles the details.

When setting up your virtual companion on HeyWaii, ensure your main prompt includes instructions on how to use the lorebook. For example, add a system prompt like:

"You are an interactive virtual companion. Rely on the provided Lorebook for world-building details. Do not invent new lore if it contradicts the Lorebook. Prioritize factual consistency."

Furthermore, your own roleplay prompts (the messages you send to the AI) should deliberately use the trigger words you set up. If you want the AI to remember a past event, organically weave the trigger word into your dialogue.

User Prompt: "Do you remember what happened back in [Eldoria]? The guards are still looking for us."

By explicitly using the trigger "Eldoria," you force the lorebook to inject the city's details into the AI's memory, ensuring a rich, context-aware response.

Advanced Tips for Building an Unforgettable AI Chatbot

To truly master AI character lorebook memory, you must treat your virtual companion as a living project that requires maintenance and updates.

First, regularly prune your lorebook. As your roleplay campaign progresses, some lorebook entries become obsolete. If a villain is defeated, update their lorebook entry from Status: Alive to Status: Deceased. If you do not update the lorebook, the AI will continue to act as if the villain is a current threat.

Second, utilize "State" entries. Create a specific lorebook entry triggered by the word "CurrentStatus" or "Inventory." Update this entry manually after major events. This acts as a bridge between the AI's short-term memory and long-term lorebook, ensuring your virtual companion always knows what they are carrying and how they are feeling.

Finally, test your triggers. On platforms like HeyWaii, you can engage in OOC (Out of Character) chats with your AI. Ask it directly: "OOC: What can you tell me about the Sunblade?" If the AI hallucinates or gives the wrong answer, your trigger words are not firing correctly, or your entry is too complex. Adjust, refine, and test again.

Conclusion

Creating the perfect AI character lorebook memory is both an art and a science. By understanding token limits, utilizing efficient formats like JSON, carefully selecting trigger words, and pairing them with strong roleplay prompts, you can engineer a virtual companion that feels remarkably human and consistent.

Gone are the days of frustrating memory lapses and broken immersion. With these engineer-approved strategies, your AI chatbot will remember every crucial detail of your shared adventures. Ready to test out your newly optimized lorebooks? Head over to HeyWaii, the ultimate destination for the latest AI games and AI character chats, and bring your unforgettable virtual companions to life today!