Full context feels safe until it isn’t. Here’s the engineering fork in the road — and real numbers from an open-source memory layer on OpenClaw. Stateless isn’t a feature. It’s the default bug. That’s the part nobody puts on the landing page: large language models don’t continue anything on their own. Every turn is a fresh sheet of paper — unless you shovel history back in. So the industry reached for two comforting reflexes: Crank the context window — pack in everything that might matter. Longer feels safer. Drop a MEMORY.md and paste it every turn — simple, auditable, easy to debug. Both are great at small scale. Both fall apart at real scale. Because context isn’t free. You pay three ways: slower, pricier, and muddier. Inference drags. Your token bill climbs linearly. Worst of all, as context grows, attention thins out in the middle — quality drops, contradictions creep in, and you’re not buying “memory.” You’re buying noise. So the real question isn’t whether to remember.…