Plugins

Plugins add panels, commands, AI tools and windows to Locus. Plugins are only available in the desktop apps.

Installing a plugin

Plugins are .lcplugin files.

1. Open Settings > Plugins and click Add plugin…, or drop the .lcplugin file on a Locus window.
2. Locus shows what the plugin is allowed to do. Check the list, then click Add.

The plugin is turned on right away. Installing a plugin with the same id as an installed one replaces it.

Only install plugins from people you trust. A plugin can do everything listed in its permissions, for example:

• read or change the construction
• open and save files you choose
• show websites in its window
• use AI features
• show a window above other apps

Managing plugins

In Settings > Plugins, use the checkbox next to a plugin to turn it on or off. To remove a plugin, click its ⓘ button, then Remove.

In Locus Classic, the Plugins menu lists the commands of all running plugins. You can search it and use it to show plugin windows and panels.

Plugins can also add keyboard shortcuts. These work system-wide, even when Locus is in the background. If another app already uses the same shortcut, the plugin’s shortcut does nothing.

Signed plugins and exams

Plugins do not have to be signed. Unsigned plugins work normally and show a Not signed badge.

During an exam, only plugins that are signed by a trusted key and made for exams keep running. They show a Runs during exams badge.

Making a plugin

A plugin is a zip archive with a plugin.json manifest, an HTML entry file and any other files it needs. The .lcplugin file extension tells Locus it is a plugin.

{
  "id": "my-plugin",
  "name": "My Plugin",
  "version": "1.0.0",
  "author": "Me",
  "main": "index.html",
  "permissions": ["construction:read"],
  "panel": { "title": "My Plugin" }
}

The main manifest fields are:

Field	Purpose
permissions	What the plugin may do: construction:read, construction:write, files, websites, assistant, exam
network	Origins the plugin may connect to. Everything else is blocked.
window, panel	A floating window and a panel in the app windows
commands	Commands shown in the Plugins menu
tools	Tools the AI sidebar and MCP clients can call
settings	Toggles, choices and text fields shown in the plugin’s settings
shortcuts	Global keyboard shortcuts
exam	Set to true if the plugin is made to run during exams

The plugin’s page talks to Locus through window.locus, which gives access to the construction, storage, settings, files, the panel and window, exam state, and handlers for commands and AI tools.

Signing

Plugins are signed with an Ed25519 key. The signature covers every file in the plugin, so sign again after each change. To have your key trusted for exams, send your public key to the Locus maintainers.