Extension Development in Nimbalyst

Nimbalyst provides MCP tools for building, installing, and hot-reloading extensions directly from within the running app. This enables rapid iteration on extension development without manually running build commands.

The recommended in-app scaffold flow uses File > New Extension Project, Developer > New Extension Project, or the Extension Developer Kit's /new-extension command. Enable Extension Dev Tools in Settings > Advanced before using the build/install workflow.

Available MCP Tools

Build Extension

mcp__nimbalyst-extension-dev__extension_build

Runs the project's build script (usually vite build) with pnpm if the project uses pnpm, npm otherwise.

Parameters:

• path: Absolute path to the extension project root (directory containing package.json and manifest.json)

Returns: Build output including any errors or warnings.

Install Extension

mcp__nimbalyst-extension-dev__extension_install

Installs a built extension into the running Nimbalyst instance. The extension must be built first.

Parameters:

• path: Absolute path to the extension project root

Returns: Installation status and any validation warnings.

Hot Reload Extension

mcp__nimbalyst-extension-dev__extension_reload

Rebuilds and reinstalls an extension in one step. This is the most common tool for iterating on extension development.

Parameters:

• extensionId: The extension ID from manifest.json (e.g., "com.nimbalyst.my-extension")
• path: Absolute path to the extension project root

Returns: Build and reload status.

Uninstall Extension

mcp__nimbalyst-extension-dev__extension_uninstall

Removes an installed extension from the running Nimbalyst instance.

Parameters:

• extensionId: The extension ID to uninstall