Tacit: Open-Source MCP Server Gives AI Coding Agents Persistent Memory

AI coding agents suffer from 'amnesia' because their reasoning and context are lost once a session ends, even though the underlying code persists in version control. This means hard-earned fixes, architectural decisions, and environment-specific workarounds can be silently undone in a new session. Tacit is an open-source, local-first Model Context Protocol server designed to address this gap by giving agents a persistent layer of institutional memory. It stores distilled decision records — including what changed, why, and causal links — in a local SQLite database with sub-millisecond retrieval, while also mirroring data as human-readable Markdown files. The project is freely available on GitHub and supports integration with editors such as Cursor and Claude Code.