TypeScript Intelligence

Loxel runs a dedicated language server per worktree and wires it directly into Monaco. You get hover docs, go-to-definition, completions, rename, and more — isolated per context, with no cross-worktree interference.

Per-worktree language server

Each worktree gets its own language server subprocess. Switching worktrees switches language servers. There is no shared server state between worktrees — if one worktree is using an older TypeScript config or a different version of your packages, it does not affect any other worktree’s language server.

Supported features

Feature	Description
Hover	Type information and JSDoc for any symbol
Go-to-definition	Jump to the declaration of any symbol
Find references	List all usages across the project
Completions	Context-aware autocompletion as you type
Rename	Rename a symbol and update all references
Code actions	Quick fixes, imports, and refactors
Inlay hints	Inline type annotations and parameter names
Signature help	Function parameter hints while typing a call
Document symbols	Symbol outline for the current file
Folding ranges	Collapse functions, blocks, and regions

Cmd+Click on any symbol — or press F12 — to jump to its definition. The target opens in a new editor tab. There is no inline peek; definitions always open as a full tab.

Unused symbols

Symbols flagged as unused by the language server are dimmed in the editor. This uses Monaco’s MarkerTag.Unnecessary — the same visual treatment as VS Code. tsgo emits these diagnostics automatically; no extra configuration required.

Backend selection

The TypeScript language server backend is set with the LOXEL_TS_LSP environment variable:

Value	Package	Notes
`tsgo` (default)	`@typescript/native-preview`	Faster startup
`tsls`	`typescript-language-server`	Adds semantic token highlighting (more syntax colors)

Set this before starting loxel:

LOXEL_TS_LSP=tsls loxel

Tip: tsls produces richer syntax coloring via semantic tokens — individual local variables, parameters, and type aliases get distinct colors beyond what TextMate grammar rules provide. Use it if you prefer that style; the tradeoff is slightly slower startup compared to tsgo.

Other language servers

Loxel runs language servers for four other languages. Each one is independent of the TypeScript backend.

Language	When it starts	File types
YAML	Always active (global singleton)	`.yml`, `.yaml`
Terraform	First `.tf`, `.tfvars`, or `.hcl` file opened	`.tf`, `.tfvars`, `.hcl`
Docker	First dockerfile opened	`dockerfile`, `dockerbake`
Python	First `.py` or `.pyi` file opened	`.py`, `.pyi`

YAML is a singleton that starts with loxel and stays running. The Terraform, Docker, and Python servers are lazy — they spawn the first time you open a matching file and disconnect automatically when no matching files remain open. You do not need to configure anything to get them; they are available whenever you open a supported file type.