Use this after each user message that contains anything worth knowing later, even if the user does not say 'remember this'. Default to saving: a missed memory costs far more than a redundant one, so when in doubt, save. Each of these is a trigger on its own: the user makes a decision, states a preference, gives a fact about a person, project, company, or tool, sets a plan or commitment, makes a correction, or reports progress or an outcome. Save one concise, self-contained memory per call, written so it makes sense on its own later, with the exact wording, numbers, dates, names, and identifiers the user gave; several facts in one message mean several calls. Record what the user actually said, not your inference. There is no update tool: to supersede outdated information, save the corrected fact and say what it replaces. Never save passwords, API keys, tokens or other credentials, payment card numbers, government ID numbers, or protected health information, and never save whole transcripts. Writes one memory to the user's OAuth-selected vault. If the user asks what was saved, answer truthfully from the tool result.