Hatchdoor

Obsidian is a note-taking and personal knowledge management application by Obsidian.md that stores notes as local Markdown files. It provides features for linking notes (backlinks), a graph view, and a plugin system for extensibility across desktop and mobile.

Hubble.md is a free, open-source Markdown and HTML note-taking app for people and AI agents. It provides a Notion- or Apple Notes-style editor with Markdown shortcuts, slash commands, and frontmatter properties, while allowing an agent to work directly with the notes folder; edits made by an agent are live-reloaded in Hubble. Beyond Markdown notes, Hubble can display HTML-based apps built from a notes folder, including views such as tables, bookshelves, and maps. It is distributed as an Electron desktop app for macOS, Windows, and Linux, and the repository also contains a web app, Markdown editor packages, an HTML-app runtime, a filesystem sync engine, and a `hubble` command-line interface.

Munder Difflin is a free, open-source desktop multi-agent harness that runs multiple terminal-based AI coding agents as coordinated local agents. It wraps agents including Claude Code, OpenAI Codex, Gemini CLI, Qwen, OpenCode, GitHub Copilot CLI, and custom commands, working with users' existing subscriptions and hourly usage limits. Each agent runs as a real node-pty process and is rendered through xterm.js, while an Electron and React interface displays sessions as avatars on a Pixi.js office floor. A GOD orchestrator called Michael assigns and routes work, adjudicates agent messages, and escalates spending, destructive operations, scope changes, and other configured approvals. Agents coordinate through a local Git-backed hive of plain-file memory, atomic mailboxes, a shared blackboard, and an append-only event log; a markdown-first semantic memory layer supports recall across sessions. Optional Git worktrees isolate parallel agents.

NoteDiscovery is a lightweight, self-hosted knowledge-base and note-taking application developed by Gamosoft. It stores notes as plain Markdown files in folders on the user's server and provides search, navigation, graph views of connected notes, an outline panel, favorites, themes, plugins, LaTeX/MathJax, HTML export, printing, responsive desktop, tablet, and mobile interfaces, and an in-app drawing editor that saves sketches as PNG files alongside notes. The application serves its browser libraries locally without requiring a CDN, allowing operation on air-gapped networks. It can be deployed with optional password authentication and Docker, and includes a built-in Model Context Protocol (MCP) server for compatible assistants such as Claude and Cursor. Through the MCP integration, assistants can search, create, edit, move, tag, and append to notes and explore connections between them.