Fixed Context Window as the Root Cause
week 1 · park, squirrels, ran two laps
… weeks of other conversations, ≈ 9K tokens and growing …
today · "remember the park?"
the whole conversation, in tokens
context window · fixed length
only this part reaches the model
outside the window → gone
"Sorry, I don't remember you mentioning the park."
a bigger window is not a fix
conversations keep growing · and nothing says who the user is
so a memory system has to answer four questions
1
what to store
becomes the storage module
tiers, pages, topic folders
2
how to update
becomes the updating module
what moves where, what is dropped
3
what to recall
becomes the retrieval module
which pages return for a query
4
how to answer
becomes the generation module
how recalled memory enters the prompt
root cause
· the model sees only what fits in the window, and earlier sessions do not
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