A universal protocol for AI agents to perceive and interact with any desktop UI.

Computer Use Protocol is a universal schema for representing UI accessibility trees, one format that works identically across Windows, macOS, Linux, Web, Android, and iOS. It includes a compact text encoding optimized for LLM context windows (~97% smaller than JSON), making it ideal for AI agents that need to perceive and act on desktop UIs.

Every platform exposes UI accessibility differently. Windows uses UIA with ~40 ControlTypes, macOS has AXUIElement with its own role system, Linux uses AT-SPI2 with 100+ roles, and the web has ~80 ARIA roles.

Today, every agent framework reinvents this translation layer independently. CUP solves it once at the representation level:

• One format everywhere - write agent logic once, run it on any platform
• Built for LLMs - compact encoding fits complex UIs into context windows at ~15x fewer tokens than the next closest format
• Built for actions - 15 canonical verbs that map to native platform APIs
• No information loss - raw native properties preserved via node.platform.*

# CUP 0.1.0 | windows | 2560x1440
# app: Spotify
# 63 nodes (280 before pruning)

[e0] win "Spotify" 120,40 1680x1020
  [e1] doc "Spotify" 120,40 1680x1020
    [e2] btn "Back" 132,52 32x32 [clk]
    [e3] btn "Forward" 170,52 32x32 {dis} [clk]
    [e7] nav "Main" 120,88 240x972
      [e8] lnk "Home" 132,100 216x40 {sel} [clk]

pip install computeruseprotocol
npm install computeruseprotocol

SDKs implement the protocol. They capture native accessibility trees, normalize them into CUP format, execute actions, and optionally expose everything through MCP servers for AI agent integration.

Building your own SDK? All you need is the spec. Implement tree capture for your target platform, normalize into the CUP schema, and you're compatible with every tool in the ecosystem.

CUP is in early development (v0.1.0). Contributions welcome — see the individual repos for guidelines.

MIT