Cortex is a persistent memory layer for AI coding tools. Every new AI chat starts from zero — you re-explain your project, your stack, your decisions, every single time. Cortex fixes that. Connect any AI tool (Claude, Cursor, Copilot, Claude Code) to your GitHub repo through one remote MCP server, and it reads your actual codebase plus a living change-history file automatically. No copy-pasting context. No re-explaining. Your AI just remembers — across tools, across sessions, across months.