Lexicon

LanguageTool is open-source proofreading software that checks spelling, grammar, and style in English, Spanish, French, German, Portuguese, Polish, Dutch, and more than 20 other languages. It detects errors that basic spell checkers may miss and can be used through a graphical interface, command line, server, HTTP API, or Java integration. The core repository is available under the LGPL 2.1 or later.

Harper is an offline, privacy-first English grammar checker developed by Automattic and written in Rust. It analyzes drafts locally, with a low memory footprint, and can be loaded through WebAssembly. The project provides integrations for Visual Studio Code, Neovim, Helix, Emacs, Zed, Obsidian, Chrome, and other browsers, along with a language server and a JavaScript package. English is currently supported, while the core is designed to be extensible to other languages.

LLM Wiki is a cross-platform desktop application maintained by nash_su that turns imported documents into a persistent, organized, interlinked knowledge base. It uses a three-layer structure of immutable raw sources, LLM-generated wiki pages, and configuration rules, with ingest, query, and lint operations; generated pages use YAML frontmatter, source traceability, an index, an operation log, and [[wikilink]] cross-references. Its ingest pipeline first analyzes each source for entities, concepts, connections, contradictions, and recommended structure, then generates or updates wiki pages, summaries, indexes, research queries, and human-review items. SHA256 caching skips unchanged files, while a persistent queue supports serialized processing, retries, cancellation, and crash recovery. It accepts PDFs, Office documents, EPUB/MOBI, Org mode, images, media, web clips, and URL batches, with optional vision-based image captions and MinerU processing for complex PDFs. Retrieval combines tokenized keyword search, optional LanceDB vector search through OpenAI-compatible embedding endpoints, and graph expansion based on direct links, shared sources, Adamic-Adar similarity, and page-type affinity. The application also provides Louvain community detection, graph insights, deep research through Tavily, SerpApi, or SearXNG, a Rust tool-using chat agent, review workflows, Mermaid and KaTeX rendering, a Chrome web clipper, and project export/import. It includes a token-protected local HTTP API and MCP server for searching, reading files, traversing the graph, rescanning sources, and calling the backend agent. The application is built with Tauri v2, React, TypeScript, and Rust, has macOS, Windows, and Linux builds, and is licensed under GPL-3.0.

Alexandrie is a self-hosted, open-source knowledge base and wiki for teams and individuals, positioned as an alternative to Notion, Confluence, and Obsidian. It uses an extended CodeMirror 6 Markdown editor with support for LaTeX, custom containers, interactive checkboxes, snippets, speech-to-text, and embedded diagram creation. Notes are organized through multi-tenant teams, workspaces, categories, and nested documents, with full-text search, a command center, integrated Kanban boards, public links, and node- or workspace-level permissions ranging from no access to owner. It is distributed as an offline-first progressive web app with synchronization, OIDC/SSO support, Docker deployment, backup and restore pipelines, and S3-compatible media and backup storage.

LLM Space v4 is a local-first desktop workbench for prototyping and developing AI agents. It lets users version prompts, system messages, tools, and model settings; trace each model call and tool run in an agent loop; replay historical runs to debug failures; and evaluate agent performance across runs. It can generate prompts and tools with AI and turn a thread into a runnable LangGraph agent. Threads, project files, and API keys remain on the user's computer, while the project describes the app as cloud-ready for managed agents. The desktop application uses Electrobun with a React, Tailwind CSS, and shadcn/ui interface, and is built as a Bun monorepo around Pi Agent Core.