Definition
Microsoft Execution Containers (MXC) is a cross-platform, policy-driven sandbox for running untrusted AI agent code on Windows, Linux, and macOS. Announced at Build 2026, it provides a unified JSON schema and TypeScript SDK (@microsoft/mxc-sdk) mapping workloads to layered containment backends.
Key Points
- Backends: ProcessContainer, Windows Sandbox, LXC, Bubblewrap, macOS Seatbelt, Isolation Session, MicroVM (roadmap)
- Agent 365 integration: Policy enforcement via Microsoft Entra and Intune
- Early adopters: github-copilot CLI, partners NVIDIA, openai, OpenClaw, Hermes, Manus
- Repository:
microsoft/mxc(MIT license, Rust + TypeScript) - Maturity: Early preview — README warns profiles should not yet be treated as formal security boundaries