Memory and Context Terms: Context Window, System Prompt, Short/Long-Term Memory, Knowledge Base, Context Engineering
~12 min read
The 6 terms covering what an agent 'knows' at any given moment — from the hard limit of its context window to the deliberate practice of shaping what it sees.
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Key points
- •Context window: the maximum information an agent can consider at once — everything else below is about what competes to fit inside it
- •System prompt: persistent background instructions that shape how the agent interprets everything else in its context
- •Short-term memory (this session only) vs. long-term memory (persists across sessions) — different lifespans, usually different storage
- •Knowledge base: general reference information, distinct from memory of the agent's own past interactions
- •Context engineering: the deliberate practice of deciding what to place in the limited context window to optimize the agent's output