Andrew Ng's open-source desktop AI coworker that delivers finished work, not just chat replies.
Free
Summary
Native macOS harness for AI agents — any model, persistent memory, sandboxed execution and cryptographic identity, fully offline and open source.
Screenshots
Description
Osaurus is a native macOS harness for AI agents. Rather than another chat wrapper around a hosted API, it is the layer around the model — agents, memory, tools, sandboxing and identity — kept entirely on your Mac. Models stay interchangeable; the context that accumulates around them does not leave the device.
Local first, cloud optional
Written in Swift for Apple Silicon with no Electron, Osaurus runs local models through optimised MLX inference and Apple's on-device Foundation Models, and connects to OpenAI, Anthropic, Gemini, xAI, OpenRouter, Ollama and LM Studio when you want more capacity. It maintains its own library of quantised models tuned for the quality-to-size trade-off on M-series chips. Fully offline operation is the default, not a degraded mode.
Agents, not just chat
Every conversation is an agent loop. Point an agent at a working folder and it gains file, search and git tools; enable the sandbox and it gets shell access inside an isolated Linux VM built on Apple's Containerization framework, with each agent given its own Linux user. Agents can browse the web in a persistent per-agent WebKit session, generate images locally, delegate bounded tasks to subagents, run on schedules, and watch folders for changes.
Memory and privacy
A three-layer memory system — identity, pinned facts and per-session episodes — distils conversations at session end and injects only the slice relevant to the current request, with a background consolidator that decays and merges rather than letting context bloat. When you do send to a cloud model, an on-device classifier flags names, emails, addresses, keys and account numbers, shows a scrubbed preview for approval, and fails closed if anything leaks past the scrub.
Extensible and interoperable
Osaurus is a full MCP server (osaurus mcp) and an MCP client that can aggregate roughly 25 remote providers over OAuth. It imports Agent Skills and full Claude plugin bundles from GitHub repositories, ships 20+ native plugins covering Mail, Calendar, Vision, XLSX, PPTX, Git and the filesystem, and exposes App Intents so "Ask Osaurus" works from Spotlight, Shortcuts and Siri.
MIT licensed and free — no subscriptions or usage caps. Requires macOS 15.5 or later on Apple Silicon.
Reviews
Similar App Suggestions
Open-source desktop app and MCP for running AI agents on your own files, an open alternative to Claude Cowork.
Freemium
Moonshot AI's assistant, known for very long context windows and strong agentic coding and research workflows.
Freemium
Meta's free assistant built on Llama, available on the web and woven into WhatsApp, Instagram, and Messenger.
Free
Perplexity's agentic browser, where an assistant sits beside every tab and can act on the pages you are looking at.
Freemium