Windows Admin-Elevated Processes Are Off-Limits to ChatGPT and Codex Computer Use — Where UIPI Draws the Line

Once you actually start using the [ChatGPT desktop app](https://chatgpt.com/download/)'s Computer Use as an AI tester on Windows, you hit a hard wall: no click or keystroke is delivered to any window belonging to an admin-elevated process. The cause is Windows' Mandatory Integrity Control (MIC) and User Interface Privilege Isolation (UIPI), which are designed to prevent a medium-integrity process from sending input to a high-integrity window at the OS level. This article walks through where that boundary sits, which tools it covers, the workarounds available in practice, and what the wall means for placing an AI tester, based on what public documentation confirms.

Reading Cua Driver 0.26.1 Computer Use Internals — Pinning the Window Target and Separating Action Facts from Postconditions

I recently wrote back-to-back code-reading tours of Hermes Agent and Open Interpreter Computer Use. Both delegate the actual OS operations to an external cua-driver, so the natural next question was what happens on that other side of the boundary. This article is that follow-up, pinned to commit b4e3caec of the trycua/cua monorepo and scoped to Cua Driver 0.26.1. It follows one request from MCP, CLI, or the in-process SDK through to the OS input API, and back out through the public ActionResult and verify_state. Along the way it walks through eight design forks: the shared native dispatch, WindowTargetGuard, element_token, ScreenCaptureKit on macOS, WGC / PrintWindow on Windows, X11 / Wayland on Linux, the closed action contract, and the three-layer permission story.

Reading Open Interpreter rust-v0.0.42 Computer Use Internals — From the QA Skill to cua-driver CLI

I recently wrote a code-reading tour of Hermes Agent v2026.9.7 Computer Use. Open Interpreter's README also documents cua-driver usage, so I wanted to know how much of the agent-side implementation is actually shared and where it diverges. This article is that follow-up: a source-only tour pinned to Git tag rust-v0.0.42, tracing one QA request through the qa-testing skill, the cua-driver CLI, and the Cua daemon, then back to the model with the result and screenshot. Along the way it hits six design forks: a QA skill embedded in the binary, delegation to external CLIs instead of a bespoke tool schema, generic command execution and approval, the view_image bridge for images, the three-layer permission story, and the reproducibility gap because pinning the OI tag does not pin the Cua version.