SearXNG is a privacy-respecting metasearch engine that aggregates results from over 100 search engines (Google, Bing, DuckDuckGo, Wikipedia, academic sources, etc.) via HTTP requests. It runs as a Flask web application, supports multiple output formats (HTML, JSON, RSS), and includes a plugin system, bot detection, rate limiting, and user preferences stored in cookies. The architecture is a monolithic Python application with a separate TypeScript/Less frontend built with Vite. It uses Valkey/Redis for caching and rate limiting, and SQLite for persistent caches. The codebase is well-structured with a clear separation of concerns: engine modules implement a common request/response interface, result types are typed with msgspec, and plugins are registered via a simple hook system. It is actively maintained with CI/CD, Docker support, and comprehensive documentation.
This repository implements an MCP (Model Context Protocol) server that bridges AI assistants with SearXNG, a privacy-respecting metasearch engine. It exposes four primary tools: `searxng_web_search` for web queries, `searxng_search_suggestions` for autocomplete, `searxng_instance_info` for capability discovery, and `web_url_read` for fetching and converting web pages to markdown. The server runs in two transport modes: STDIO (default) for simple MCP integration, and HTTP for stateful/stateless remote access with optional OAuth and static bearer authentication. The architecture is modular and security-focused. Core modules include a proxy layer with per-type agent selection, SSRF protection via private IP blocking and DNS rebinding detection, a browser solver chain (FlareSolverr/Byparr) for challenge solving, worker-threaded PDF extraction, and multi-instance failover/fanout for SearXNG replicas. All credential-bearing output (logs, errors, MCP resources) is redacted by a centralized sanitizer. Extensive environment-variable configuration (~40+ knobs) controls caching, timeouts, rate limiting, TLS, and result formatting. Highlights include a strict integer parser that rejects unsafe or malformed values, an LFU cache with age tie-breakers and configurable TTL, and a comprehensive URL security module covering both IPv4 and IPv6 private ranges. The test suite achieves over 90% line coverage and includes integration, unit, fuzz, and e2e tests, with documentation tests that verify README and configuration docs match source contracts. The project is actively maintained with frequent releases, pinned dependencies, and a verification gate that enforces zero-vulnerability audits before publishing.
Vane is a privacy-focused, self-hosted AI answering engine that combines web search with large language models (LLMs) to produce cited, real-time answers. The system is built as a Next.js 16 application with a React frontend and a set of API routes that orchestrate a multi-step research pipeline: classification of user queries, parallel execution of search actions (web, academic, social, scrape, upload-based retrieval), widget generation (weather, stock, calculation), and final answer synthesis via an LLM. It supports multiple LLM providers (OpenAI, Anthropic, Gemini, Groq, Ollama, LM Studio, etc.) through a clean provider abstraction, and stores chat history in a local SQLite database managed by Drizzle ORM. The architecture is a monolith with clear separation of concerns: a model registry for LLM/embedding providers, a search agent with an action registry pattern, a widget system for structured data display, and a configuration manager that persists user settings to a JSON file. The frontend uses client-side streaming via EventSource to display research progress and final answers in real-time. Deployment is Docker-first, bundling a SearXNG instance for privacy-respecting web search, with multi-arch images and a slim variant. Key entry points include the main chat page (`/`), individual chat pages (`/c/[chatId]`), a news discovery page (`/discover`), and a library for uploaded documents. The primary API endpoints are `POST /api/chat` (streaming chat), `POST /api/search` (non-streaming search), and various CRUD routes for providers, config, and uploads. External dependencies include SearXNG (self-hosted), Open-Meteo (weather), Yahoo Finance (stocks), and the LLM provider APIs. The codebase demonstrates strong engineering practices with well-defined abstractions, a modular agent architecture, and a focus on privacy and local-first operation. It is actively maintained with a large community, though some areas (custom migration runner, large chat hook) show room for refinement.
Morphic is a self-hostable AI answer engine and chat application. In production it streams LLM research results into a rich chat UI: it runs an agentic researcher loop that calls search tools (SearXNG, Tavily, Brave, Exa, Firecrawl), fetches and extracts page content, allocates numbered citations, and emits a JSONL-based 'spec' stream that a generative UI renderer turns into structured cards, grids, headings, buttons, and inline images. Alongside the core chat it ships usage-budget metering, guest/anonymous chat, file uploads to S3-compatible storage, a notes/library feature, feedback collection, model discovery and selection, chat sharing, admin invitations, and an analytics relay that forwards scrubbed PostHog events without exposing authentication tokens.
Local Deep Research is a self-hosted, privacy-focused AI research assistant that performs deep, agentic research using multiple LLMs and web searches. It provides a full-stack web application (FastAPI + JavaScript), a programmatic API, and a Model Context Protocol (MCP) server. The system ingests user queries, decomposes them, executes parallel searches across web and academic sources (SearXNG, Google, arXiv, PubMed, Semantic Scholar, etc.), fetches and extracts content, evaluates evidence, and synthesizes reports with citations. It features per-user encrypted SQLCipher databases, a settings system with environment variable overrides, a RAG library with FAISS vector store, journal quality scoring, news subscriptions, and extensive security controls (egress policy, SSRF protection, credential scrubbing). The codebase is heavily tested with unit, integration, UI, accessibility, and security tests. It is a hybrid of a web application and a research data pipeline, but the dominant character is a production-grade application.
CoexistAI is a research assistant framework implemented as a FastAPI application that provides a suite of API endpoints for web search, YouTube and Reddit retrieval, geospatial mapping, git repository analysis, text-to-speech/podcast generation, and knowledge base creation from local files or crawled websites. It integrates with an MCP server for agentic workflows and supports pluggable LLMs (Google, OpenAI, Ollama, local) and embedders (Google, HuggingFace, Infinity). The architecture is monolithic with modular utility functions, containerized via Docker with a companion SearxNG instance for privacy-respecting search. The codebase demonstrates a hybrid nature: while primarily an application with explicit API entry points, its core purpose is to support research and data-gathering tasks, making it equally relevant for data research scenarios. Configuration is centralized, and the system includes a web-based admin UI for runtime parameter changes. Active development is evident from recent commits and numerous utility modules, though some global mutable state and fallback-heavy code indicate where the system has evolved rapidly.