Agent memory

Plain English. What an agent retains between sessions: facts about you, past decisions, project state. Distinct from the context window (working memory that vanishes when the session ends) — agent memory is the part deliberately written down and carried forward.

Why it moves money. Memory is the claimed moat of nearly every agent product: the longer it works with you, the harder you are to poach. But production practice keeps converging on aggressively simple substrates — versioned Markdown folders, portable zip-of-markdown formats — which commoditises the layer a wave of memory startups is priced on. Meanwhile labs are wiring memory across their own surfaces, which strengthens platform lock-in from the other direction.

What to watch. Whether memory stays a portable file you own or becomes provider-held state you can't export — that single design question decides where the moat sits.

From the signals. Memoryfields: a proposal to make agent memory a file format, not a pipeline. Extency: production agent memory is versioned Markdown folders, not vector databases. Claude's memory went cross-surface, with sensitive topics off by default.