How to uninstall Msty Studio on Mac

Msty Studio's desktop app installs as MstyStudio.app and keeps its local data in ~/Library/Application Support/MstyStudio. Local models, often several gigabytes each, can live somewhere else, depending on the engine that runs them, so look up each model's location in the app before you remove anything, and export the conversations and workspaces you want to keep. These steps cover Msty Studio Desktop downloaded from msty.ai and the Homebrew cask mstystudio.

Export your data and note where models are

  1. Export everything once: in Msty Studio's Settings, use Export Data, which Msty's backup page describes as a zip file with all of your data. To move a single workspace, right-click its icon and choose Export Workspace.
  2. Open Model Hub › Local Models › Installed. Msty's local models page says this list shows each model's engine, Ollama, MLX or Llama.cpp, and its location. Write down the locations, and uninstall models you no longer want from the same list; that frees their disk space in a way the app understands.
  3. If you have an Aurum license, Msty's download page notes that Studio Desktop counts against your activated devices limit and that you may need to deactivate a device when you reach it. Removing the app is not a deactivation.

The older Msty App (1.x) is a separate installation, according to the same download page. Removing Msty Studio does not remove it, and removing it does not touch Msty Studio.

Quit Msty Studio and remove the app

  1. Quit Msty Studio from its application menu.
  2. Search Activity Monitor for MstyStudio and check that the app and its helper processes have exited.
  3. Move MstyStudio from the Applications folder to the Trash.

Where Msty Studio keeps its data

Location What it holds What to do
~/Library/Application Support/MstyStudio The app's local data Keep it until your export is verified; remove it only when you are done with Msty Studio
~/Library/Logs/MstyStudio App logs Safe to remove after quitting
~/Library/Preferences/MstyStudio.plist App preferences Safe to remove for a clean reinstall
The model locations you noted Local models Decide per model; a folder outside these paths is not removed with the app

Msty's documentation does not name these folders. They come from the Homebrew cask's zap list and this test, where the support folder was about 5 MB after a first launch with no models.

Check the result

Run these read-only commands in Terminal:

pgrep -lf MstyStudio.app
ls -d "$HOME/Library/Application Support/MstyStudio"
du -sh "$HOME/Library/Application Support/MstyStudio"
  • No output from pgrep means no process is running from MstyStudio.app. A listed process means the app or one of its helpers is still open.
  • ls -d printing the path means Msty Studio's data is still on this Mac, which is expected if you kept it. "No such file or directory" means it is gone.
  • du -sh shows how much space that folder takes. Also check the model locations you wrote down; a model elsewhere will still take its space.

For other local model tools, see How to Delete Ollama and LM Studio Models on Mac.

If you installed it with Homebrew

Mole skips --zap when its list reaches unchecked or shared data, or cannot be fully checked, and still cleans the leftovers you selected.

The mstystudio cask's zap list includes ~/Library/Application Support/MstyStudio, logs, preferences, saved window state and crash reporter files. Running brew uninstall --cask --zap mstystudio yourself moves them to the Trash, whatever you ticked in Mole. To keep your data, export it first, or remove only the app:

brew uninstall --cask mstystudio

What Mole lists

This is how Mole handles Msty Studio installed from the official download:

  • ~/Library/Application Support/MstyStudio is listed but not selected. The rebuildable caches inside it, Cache, Code Cache, GPUCache, DawnGraphiteCache, DawnWebGPUCache and blob_storage, are separate rows selected by default.
  • ~/Library/Logs/MstyStudio and ~/Library/Preferences/MstyStudio.plist are selected by default.
  • Model folders outside these paths were not part of the test, so this guide makes no claim about them.

What this test covered

On September 26, 2026, Msty Studio 2.9.11 was installed from the official package Homebrew's cask points to, checked against its checksum and copied into Applications, launched once without signing in or installing a model, and uninstalled with a development build of Mole with every listed row ticked, including the ones Mole leaves unchecked. Mole's Status page showed MstyStudio as one row with six processes. The app (757 MB), the support folder and its caches, the logs and the preferences, 10 items in all, went to the Trash, and none of them was still on disk afterwards. No login item or launch agent appeared, and the Homebrew cask was not uninstalled. An earlier test on September 22, 2026 removed the app and its 5.5 MB support folder the same way.