SecondBrain is a self-hosted, local server written in Swift, designed to empower AI assistants like Claude Desktop and Claude Code with direct access to your personal knowledge vault. It facilitates comprehensive Create, Read, Update, Delete (CRUD) operations for Markdown notes, automatically tracking every edit with Git for robust versioning. Additionally, it provides read-only access and full-text search capabilities across your PDF reference library. Built for privacy, performance, and efficiency, SecondBrain ensures all your data remains on your machine, boasts instant startup times, minimal memory usage (~15 MB), and works seamlessly alongside other Markdown editors like Obsidian or iA Writer.
Key Features
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02Disk-based grep for instant, efficient full-text search across all content.
03Read-only access and full-text search across hundreds of PDFs.
04Full CRUD operations for Markdown notes with automatic Git versioning and soft deletes.
05Image-based PDF reading with page navigation and outline support.
06Secure operations with path validation, symlink resolution, and no arbitrary shell execution.
Use Cases
01Connecting a personal Markdown note vault and PDF library to an AI assistant for enhanced knowledge retrieval and content creation.
02Maintaining a version-controlled digital second brain for research, journaling, or project documentation.
03Providing AI-powered access to existing local notes and reference materials without compromising data privacy.
