Code intelligence¶

The model navigates code with grep by default. In a large codebase that's imprecise (the same names appear everywhere), every extra file it reads costs context, and type errors only show up when the build runs. With a language server installed, lcode does better:

An lsp tool. The model asks where a symbol is defined, where it's used, what its type or signature is, or what a file contains, and gets exact path:line answers.
Errors after edits. After the model changes a file, the language server checks it, and any errors the change introduced are added to the result of the edit, so the model fixes them right away:

● edit_file(src/main.ts)
  ✓ Edited src/main.ts
  Edited src/main.ts (1 replacement(s)). Result: …
  [The language server found 1 new error after this change:
    main.ts:3: Argument of type 'string' is not assignable to parameter of type 'number'. (typescript)]

Only errors the edit introduced are listed, not ones that were there before, and warnings are left out. Only the edited file is checked: errors a change causes elsewhere (in the callers of a function whose signature changed, say) show up when the model runs the build or the tests.

Setting it up¶

Install a language server for your language; lcode finds it on the PATH, or in the project's node_modules/.bin:

Language	Server	Install
Python	basedpyright, pyright or pylsp	`uv tool install basedpyright` (or `npm install -g pyright`)
TypeScript, JavaScript	typescript-language-server (TypeScript 5), or `tsc --lsp` (TypeScript 7)	`npm install -g typescript-language-server typescript`
Go	gopls	`go install golang.org/x/tools/gopls@latest`
Rust	rust-analyzer	`rustup component add rust-analyzer`
C, C++	clangd	`apt install clangd`, or `brew install llvm`

lcode doctor shows what it found. Servers start the first time they're needed in a session, one per language, and stop when you quit. Without any server installed, nothing changes: there's no lsp tool and nothing about it in the model's instructions.

TypeScript 7 no longer includes the tsserver.js that typescript-language-server needs, but its own tsc --lsp is a language server; lcode tries one after the other.

The tool¶

Action	What the model gets
`definition`	Where the symbol is defined: `src/calc.py:12: def add(a, b):`
`references`	Every place it's used, one line each
`hover`	Its type or signature, and documentation
`symbols` with a path	The file's outline: classes, functions, methods, with line numbers
`symbols` with a query	Symbols with that name anywhere in the workspace

The model gives a line number and the symbol's name on that line (models rarely know column numbers). The tool is available to subagents and in plan mode too.

Settings¶

Setting
`lsp`	`auto` (default): use the language servers that are installed; `off`: never

~/.config/lcode/lsp.json picks another command for a language, or turns one off:

{
  "python": {"command": ["pylsp"]},
  "rust": {"disabled": true}
}

A language server's own output goes to ~/.local/state/lcode/lsp-logs/<language>.log. Language servers run on your machine even when the sandbox is on: they only read the project.