Osaurus

Osaurus: AI agents that never leave your Mac

Osaurus is an open-source (MIT) native macOS harness for AI agents, written in Swift for Apple Silicon: open models run entirely on your machine, so prompts, files, and memory never leave it — and it works fully offline. Cloud models (ChatGPT, Claude, Gemini, Grok) can be added per-task when you want them, with one persistent shared memory carried across local and cloud models alike. The project's GitHub repo passed 7,300 stars and 185,000 downloads within a year of its August 2025 creation, reaching #2 Product of the Day on Product Hunt with no paid marketing.

What separates Osaurus from a model runner is the agent layer: it acts as a full Model Context Protocol (MCP) server and ships 20+ native plugins — Mail, Calendar, Browser, Vision, Git, filesystem — so agents can do real work on the Mac, including autonomous execution like folder watching, file reading, and voice control, inside a hardware sandbox.

Key Features

• Runs local models on Apple Silicon via a Swift-native engine; fully offline capable
• Full MCP server with 20+ native macOS plugins (Mail, Calendar, Browser, Vision, Git)
• Persistent shared memory across local and cloud models
• Autonomous agent execution: file reading, folder watching, voice control
• Compatible with LM Studio, Ollama, and MLX model directories; custom quantization
• MIT-licensed, no subscription or usage caps; install via .dmg or brew install osaurus

Ideal Use Case

A Mac user — developer or privacy-conscious professional — who wants agents that read mail, watch folders, and automate local workflows without any of it transiting a cloud API. Requires an Apple Silicon Mac on macOS 15.5+.

How Osaurus differentiates

Ollama runs models; Osaurus runs agents — MCP server, OS-integrated plugins, persistent memory, and autonomous execution on top of local inference (it can even consume your existing Ollama model directory). Against LM Studio, it is open source rather than proprietary freeware, and automation-focused rather than chat-UI-focused. Production credibility: 7.3K+ GitHub stars and 185K downloads in under a year, entirely word-of-mouth; co-founder Terence Pae spent ~20 years shipping software at Netflix, Tesla, and Zillow.

FAQ

Is Osaurus really free? Yes — MIT-licensed open source with no subscription or usage caps. Optional cloud models use your own provider accounts.

What Macs does Osaurus support? Apple Silicon only, on macOS 15.5 or later; there is no Intel or Windows version.

Does Osaurus work offline? Fully — local models run on-device and nothing requires a network connection.

How does Osaurus relate to MCP? It functions as a complete MCP server, exposing its 20+ native plugins to any MCP-capable agent or client.

tl;dr

Osaurus is the open-source agent harness Apple Silicon deserved: local models, real macOS integration through 20+ plugins and MCP, persistent memory, and zero data leaving the machine — free under MIT, with 7.3K stars to show for it.

Related

Looking for more options? Browse the Developer Tools directory or read our best AI coding tools listicle. Osaurus is also tracked on Crunchbase.