add_preference
Adds a new preference given the name, value and type.
LABSCO SUMMARY
This turns a feature flag or a cached login into a single call against a real device, which is the fastest route to an app state that would otherwise take a full sign-up flow to reach.
The tool set is deliberately literal — device, app, file, key — and each step returns exactly what the next one needs as an argument. add_preference asking for a type is the detail that matters in practice, because the stored type is what the app reads back and a string written where a boolean belongs will not behave. Nothing here keeps a copy of what you overwrote, so a read_preferences call before the change is the only record of the previous state you will have.
What it is
An editor for the preference files of apps installed on connected Android devices: walk from device to app to file, read what is stored, and change it in place.
What you get
- A path from hardware down to a stored value: devices lists the connected Android devices, list_apps lists the apps installed on a device, list_files lists an app's preference files, and read_preferences returns every user preference in a chosen file.
- Writes at the level of a single key: change_preference sets the value of an existing preference by name, add_preference creates a new preference from a name, value and type, and delete_preference removes it.
- Every call is addressed the same way — deviceId, appId and filename — so a value can be changed on a chosen device and file without touching another.
Requirements
A connected Android device with the app installed on it. Every call is addressed by deviceId, appId and filename. No credentials are configured.
Setup effort
One command — npx -y @charlesmuchene/pref-editor-mcp-server
USE CASES
01
Flipping a stored value without a rebuild
Pick the connected device, find the app and its preference file, read what is in there, and change the one value you are after. The build on the device stays as it is.
02
Putting an app into a state you need to test
Add a preference the app has never written, remove one to see what it does on a fresh install, and read back what the app is actually holding rather than what you think it is.
7 tools
Counted once with only startup setup. Other versions, modes or optional credentials may expose a different list.
change_preference
Changes the value of an existing preference
delete_preference
Delete an existing preference
devices
Lists connected Android devices
list_apps
Lists apps installed on device
list_files
Lists preference files for an app
read_preferences
Reads all user preferences in a file
BEFORE YOU INSTALL
What to know first
Tools you get
7 tools when we connected.
Requires
- npx on PATH
- Node.js 14+
CONTEXT COST
Light Standing cost
Rated by the size of the 7 tool definitions that ride along on every turn, not by how many there are
INSTALLATION
Connect your client
Add the block to your client, or run the command directly.
Server setup
Configuration file
JSON
{
"mcpServers": {
"pref-editor-mcp-server": {
"command": "npx",
"args": [
"-y",
"@charlesmuchene/pref-editor-mcp-server"
]
}
}
}npx
TERMINAL
npx -y @charlesmuchene/pref-editor-mcp-server
