PiecesOS is the lightweight, always-on background service that powers every Pieces application and plugin. It runs quietly on your machine, orchestrating local data processing and managing the machine learning models that enable the core AI features of the Pieces suite. PiecesOS acts as the local service layer and API hub, exposing a secure HTTP/IPC API that the Desktop App, IDE extensions, and any MCP-capable client can use to interact with your on-device context and memory.

As the core dependency for all Pieces functionality, PiecesOS drives the three pillars of the Pieces experience: Pieces Drive (asset management), Pieces Copilot (grounded AI assistance), and Workstream Activity views. Whether you’re using the Desktop App, browser extensions, or IDE plugins, PiecesOS is the engine that brings AI-powered context, memory, and productivity to your workflow—while keeping your data safe, local, and fully under your control.