Stem is a persistent cross-AI memory. Connect it once and ChatGPT can store distilled memories (decisions, facts, preferences, project context), recall the most relevant ones in any future chat, link related ideas into a typed knowledge graph, and see it all visualized at awase.dev/stem. The same memory is available to every MCP-compatible tool the user connects, so context never has to be re-explained. Free tier included; storage tiers are opt-in.