MCPB
One-click local MCP server installation in desktop apps
MCPB (MCP Bundles) defines a packaging format and toolchain for one-click installation of local Model Context Protocol (MCP) servers in desktop apps like Claude for macOS and Windows. An .mcpb file is a zip archive containing your server and a manifest.json that declares capabilities, entry points, permissions, and configuration inputs, much like how .crx packages Chrome extensions or .vsix packages VS Code extensions. The goal is to make local tool servers easy for end users to install, update, and configure, while giving app developers a consistent way to discover and load them safely. The repository includes the bundle spec, a CLI to scaffold and pack bundles, and the loading/verification code used by Claude’s desktop apps, including support for auto-updates and a curated directory. It supports multiple implementation styles—Node.js, Python, or native binaries—and provides guidance on bundling dependencies so bundles run out-of-the-box.