Memory & Context

Engineering the Context Window

Treat the finite window as a budgeted resource: per-category token budgets, position-aware ordering, and utilization metrics.

Short-Term vs Long-Term Memory

The in-prompt working set vs the external store: what earns a slot, when to write, when to recall, and the promotion/demotion cycle.

Memory Types: Episodic, Semantic, Procedural

Three durable memory kinds plus the scratchpad, each written and retrieved differently; reflection promotes episodes to semantics.

Retrieval-Augmented Memory

Recall as retrieval: state-derived cues, relevance+recency+salience scoring, threshold-before-truncate, and provenance-tagged rendering.

Context Compaction & Hierarchical Memory

The compaction ladder, task-structured summarization, MemGPT-style tiering, pressure-triggered hysteresis, and verifying lossy compaction.

Memory Stores: Vector, KV, Graph & Eviction

Match backend to memory kind, a unified interface, why unbounded stores rot retrieval, and decay/eviction policies.

Evaluating Memory Quality

Memory-specific metrics (recall@k, staleness, constraint survival, write precision) and the pitfalls they catch: poisoning, staleness, drift, compaction amnesia.