How We Built an AI Second Brain for 60K Knowledge Workers
Original URL: https://medium.com/@AnalyticsAtMeta/how-we-built-an-ai-second-brain-for-60k-knowledge-workers-78c507dd795b
Article Written: April 29, 2026
Added: May 16, 2026
Type: project
Summary
The article discusses the development of an AI Second Brain at Meta, designed to assist knowledge workers by providing structured access to their work context across various platforms. It outlines the architecture, including the PARA workspace method, infrastructure layer, execution engine, and reusable skills. The project has seen rapid adoption, with over 63,000 users leveraging the AI to streamline workflows and enhance productivity. Key lessons learned include the importance of infrastructure, progressive disclosure of information, and community-driven feature development.
💠Your Thoughts
My hightlight points: An AI agent is more than a model. It is a model plus a harness: the execution environment, tools, and orchestration logic that turn a question-answering system into a work engine. A capable harness provides the agentic loop (reason, act, observe, repeat), filesystem access, tool calling, MCP integration, and error recovery.