🧠 pi-lsp — Shared Language Server Tools for Pi

@narumitw/pi-lsp is a native Pi coding agent extension that exposes Biome, ty, and Ruff language-server tools through one shared LSP runner Module.

It supersedes the older split packages @narumitw/pi-biome-lsp and @narumitw/pi-python-lsp, which now live under extensions/deprecated/ and are excluded from active workspace scripts.

✨ Features

• Runs biome lsp-proxy on demand for diagnostics, formatting, import organization, and source fixes.
• Runs ty server on demand for Python type diagnostics.
• Runs ruff server on demand for Python lint diagnostics, formatting, import organization, and source fixes.
• Uses one internal LSP runner for JSON-RPC framing, subprocess lifecycle, diagnostics, formatting, code actions, and workspace edit application.
• Keeps Biome, ty, and Ruff behavior in small server Adapters.
• Supports workspace roots, file limits, recursive file discovery, and write-or-preview edits.
• Starts language servers only for tool calls, then shuts them down.
• Shows statusline activity only while LSP tools are running.

📦 Install

pi install npm:@narumitw/pi-lsp

Try without installing permanently:

pi -e npm:@narumitw/pi-lsp

Try this package locally from the repository root:

pi -e ./extensions/pi-lsp

⚠️ Tool-name compatibility

This package intentionally registers the same tool names as @narumitw/pi-biome-lsp and @narumitw/pi-python-lsp:

• biome_lsp_diagnostics
• biome_lsp_format
• biome_lsp_fix
• ty_lsp_diagnostics
• ruff_lsp_diagnostics
• ruff_lsp_format
• ruff_lsp_fix

Avoid installing @narumitw/pi-lsp side by side with the older deprecated LSP packages unless you have verified how your Pi version handles duplicate tool names.

✅ Requirements

Install the language servers you want to use somewhere on PATH:

uv tool install ty
uv tool install ruff

For Biome, either install it globally/on PATH, add your project's node_modules/.bin to PATH, or point the extension at a project-local command. For example:

npm install -D @biomejs/biome
PI_BIOME_LSP_COMMAND="./node_modules/.bin/biome lsp-proxy" pi -e ./extensions/pi-lsp

Or provide custom server commands:

PI_BIOME_LSP_COMMAND="npx biome lsp-proxy" \
PI_TY_LSP_COMMAND="uvx ty server" \
PI_RUFF_LSP_COMMAND="uvx ruff server" \
pi -e ./extensions/pi-lsp

Optional timeout overrides:

PI_BIOME_LSP_TIMEOUT_MS=30000 \
PI_TY_LSP_TIMEOUT_MS=30000 \
PI_RUFF_LSP_TIMEOUT_MS=30000 \
pi -e ./extensions/pi-lsp

🛠️ Pi tools

Biome

• biome_lsp_diagnostics — start biome lsp-proxy, open supported files, and return diagnostics.
• biome_lsp_format — compute or write formatting edits for one Biome-supported file.
• biome_lsp_fix — compute or write source actions such as source.fixAll.biome or source.organizeImports.biome.

Python

• ty_lsp_diagnostics — start ty server, open Python files, and return type diagnostics.
• ruff_lsp_diagnostics — start ruff server, open Python files, and return lint diagnostics.
• ruff_lsp_format — compute or write Ruff formatting edits for one Python file.
• ruff_lsp_fix — compute or write Ruff source actions such as source.fixAll.ruff or source.organizeImports.ruff.

🚀 Examples

Check a project subset with Biome diagnostics:

{
  "paths": ["src", "extensions/pi-lsp/src"],
  "limit": 100
}

Format a TypeScript file with Biome:

{
  "path": "src/index.ts",
  "write": true
}

Check a Python project with ty or Ruff diagnostics:

{
  "paths": ["src", "tests"],
  "limit": 100
}

Organize Python imports with Ruff:

{
  "path": "src/app.py",
  "kind": "source.organizeImports.ruff",
  "write": true
}

If paths is omitted for diagnostics, the tool recursively discovers supported files under the workspace root while skipping common generated, dependency, cache, and virtualenv directories.

💬 Command

/lsp

Shows the configured Biome, ty, and Ruff LSP commands and whether each command is available on PATH.

🗂️ Package layout

extensions/pi-lsp/
├── src/
│   ├── adapters.ts
│   ├── command.ts
│   ├── files.ts
│   ├── lsp-client.ts
│   ├── pi-lsp.ts
│   ├── runner.ts
│   ├── text-edits.ts
│   └── types.ts
├── README.md
├── LICENSE
├── tsconfig.json
└── package.json

🔎 Keywords

Pi extension, Pi coding agent, Language Server Protocol, Biome LSP, ty, Ruff, Python LSP, formatter, linter, import organization, AI coding tools.

📄 License

MIT. See LICENSE.