Rapier
Create and edit Markdown notes, diagrams, drawings, and watercolor art with real-time AI agent collaboration via MCP.
Rapier is an offline-first, portable Markdown editor and creative canvas that bundles writing, vector sketching, and digital watercolor painting into a single lightweight file. Operating seamlessly across Android, web, desktop, and standalone HTML, Rapier stores everything—including diagrams, checklists, LaTeX formulas, and compressed JPEG XL images—directly within standard Markdown files. Through native Model Context Protocol (MCP) and WebMCP support, AI agents like Claude and ChatGPT can interact with and co-edit documents in real time, giving users full visibility and version control over automated changes alongside powerful embeddable components for custom applications.