LSP Manager

Cosine CLI includes a built-in LSP Manager for Mason-managed language tooling.

Use it to:

• install and remove language servers
• update installed Mason packages
• install and update the Mason registry source
• filter packages by category (All, LSP, DAP, Linter, Formatter)

Open the LSP Manager

You can open it in two ways:

• ctrl+alt+l
• / → LSP servers

Layout and navigation

At the top of the dialog you can switch sections:

• (1) All
• (2) LSP
• (3) DAP
• (4) Linter
• (5) Formatter
• (6) Registries

Switch with either:

• number keys 1 to 6
• tab / shift+tab

Other controls:

• ↑ / ↓ — move selection
• pgup / pgdown — jump faster
• type — filter packages
• backspace — edit filter
• esc — close dialog

Install and remove packages

In package sections (All, LSP, DAP, Linter, Formatter):

1. Select a package.
2. Press enter.

If the package is not installed, this installs it. If it is installed, this removes it.

Update managed packages

Press U (uppercase) to update all currently installed Mason-managed packages.

This re-runs installation for installed packages against the currently loaded registry metadata.

Registry management

Open the Registries tab (6) to manage the Mason registry source.

By default, the manager exposes:

• mason-org/mason-registry
• https://github.com/mason-org/mason-registry

Actions:

• enter — install the registry (if missing)
• u — update the installed registry

After installation/update, package lists refresh from registry package.yaml data.

Important behavior

Cosine CLI does not auto-install LSP servers during normal LSP operations.

If a server is missing, install it explicitly in the LSP Manager.