LessAI is a Tauri 2 desktop application for AI-assisted document rewriting. It supports importing documents in plain text, Markdown, LaTeX, DOCX, and PDF formats, segmenting them into rewrite units, and sending them to an OpenAI-compatible LLM for rewriting. The system provides a workbench view with a side-by-side editor and review panel, enabling users to view diff hunks, accept/reject suggestions, and finalize writeback to the original file. For complex formats like DOCX and PDF, a slot-based model preserves locked placeholders (e.g., tables, images, hyperlinks) while allowing editable text regions to be rewritten. The application includes a web demo mode for plain text only, a full settings UI for provider configuration, and an in-app update mechanism. The architecture is a monolith split between a Rust backend (Tauri commands, document adapters, rewrite pipeline) and a React/TypeScript frontend with custom hooks, progressive rendering, and a slot-based structured editor. The codebase is well-structured with extensive unit tests, roundtrip test fixtures, and CI/CD pipelines for cross-platform bundles.