AI Overlay Tools Explained How They Work

AI overlay tools render an AI chatbot in a private window that sits on top of other applications but remains invisible to screen capture and monitoring software. Here is how they work.

An AI overlay tool creates a window using operating-system APIs that exclude it from screen capture pipelines. On macOS, this relies on a system-level window privacy mechanism. The window is physically rendered by the GPU and visible to the user, but capture and enumeration APIs cannot see it. The overlay embeds an AI client that loads ChatGPT or Claude. A keyboard relay captures keystrokes and routes them to the embedded client. Fracture is the most mature implementation, offering hotkey toggling, transparency control, and multiple AI provider support.