Windows · Local-first · Zero telemetry
Ghost sits over whatever you are doing. It hears the conversation, reads the window you point it at, and answers in a translucent overlay that screen sharing does not capture — without switching windows or pasting anything.
Runs with no API key at all using the built-in offline provider. Add a free Groq key for real answers.
ThemWhat’s the time complexity of that approach?●
O(n log n) — the sort dominates. The scan after it is linear, so it does not change the bound.
If the input is already sorted, or you can afford a hash set, you can get this to O(n)
Ctrl + Space
Summon the overlay from any application, type, and read a streamed answer without leaving the window you were in. Escape puts it away.
Answers are as short as the question deserves. Four response lengths, and the shortest routes to a faster model so a quick question stays quick.
Live transcription
Captures what your computer is playing — the other people on a call — transcribes it, and answers questions as they are asked, without being prompted.
Only the other party's speech triggers an answer, and only when it parses as a question. Acknowledgements and thinking aloud are transcribed but ignored.
Local OCR
Reads the text in a window you pin — your editor, a document, a terminal — and answers about what is actually there.
Text is extracted on your machine by the OCR engine built into Windows. The screenshot never leaves the device; only the text becomes context, and only when you ask.
Content protection
The overlay is excluded from screen capture and recording, so sharing your screen shares everything except Ghost.
Built on the documented Windows API for exactly this. Ghost includes a self-test that measures whether it is genuinely working on your machine, and reports the limits rather than a reassuring tick.
There is no Ghost server. Nothing is collected, and there is no analytics setting to opt out of, because the feature does not exist. Every capture source is off until you turn it on, and the status bar shows what is actually running — not what is configured.
On the invisible overlay
Ghost asks Windows to exclude its own window from screen capture, using the same documented API that banking and DRM applications use. It works with Zoom, Teams, Meet and Slack. It is not a security bypass — it hides nothing but its own window, and Microsoft is explicit that it offers no guarantee. A camera pointed at your screen still sees everything. Ghost ships a self-test so you can measure it on your own machine rather than take that on trust.
Download and run the installer.
Ghost_0.1.0_x64-setup.exe. Installs for the current user, so it never asks for administrator rights.
Press Ctrl+Space from anywhere.
Ghost starts in the tray with no window. The hotkey summons it; Escape puts it away.
Add a provider key, or don't.
The offline provider answers without any key, so you can try the whole interaction first. Settings → AI Models connects Groq, xAI, Ollama, or anything OpenAI-compatible.
Turn on what it may use.
Settings → Privacy. System audio to hear a call, screen reading to read a window. Both are off until you enable them.