Living Brain is a persistent, self-learning memory layer designed to give AI agents shared context, continuity, and non-obvious connections across more than 60 AI platforms. It stores knowledge outside the model and retrieves relevant context at inference time, reducing token usage by up to 22.6 times and cutting per-task costs by 95% compared to full-context baselines. The platform is compatible with Claude, ChatGPT, Cursor, and many others, and is accessible via API, SDK, and MCP. Living Brain also supports post-training workflows by curating accumulated knowledge and task outcomes into fine-tuning datasets.