# memory.rs — Memory Engine & Recall

#### 📦 Core Structs

```rust
pub struct Memory {
    pub text: String,
    pub timestamp: u64,
    pub tags: Vec<String>,
    pub emotion_vector: EmotionVector,
    pub importance: f32,
}

pub struct MemoryManager {
    pub memories: Vec<Memory>,
}
```

* Each memory has emotional metadata and a subjective importance score.
* Memories decay over time unless reinforced.

***

#### 🔍 Recall Logic

The core method for memory retrieval is:

```rust
fn recall(&self, query: &str, top_k: usize) -> Vec<Memory>
```

It uses:

* TF-IDF-style string similarity
* Emotion vector alignment (valence-aware)
* Recency and priority weighting

> Recall is weighted so emotionally significant or frequently accessed memories are more likely to surface.

***

#### 🧠 Writing New Memories

You can store memories manually:

```rust
agent.memory.store("He gave me the crystal.", Some("important"));
```

Or let them be auto-written after every LLM response via `Agent::receive_input`.

***

#### 🔁 Memory Decay & Compression (WIP)

Future roadmap includes:

* Memory decay based on age & access
* Compression of low-priority memories
* Persistent DB-backed memory

***

#### 💡 Use Cases

* Agent remembers specific player actions
* NPC personalities evolve over time
* Behavior changes based on past relationships