pi-lsp

A pi extension that gives the AI agent access to real-time LSP diagnostics.

Features

• Auto-append on read — Diagnostics are automatically appended when pi reads a file with issues, so the agent sees errors and warnings in context
• Standalone diagnostics tool — The LLM can query diagnostics for any file on demand, useful after edits or to inspect a file's health
• Lazy & eager startup — LSP servers matching the cwd spawn at session start; others spawn lazily on first relevant file read
• Nvim-style activation — Each LSP has a condition function that checks for root markers (e.g., tsconfig.json, Cargo.toml) before spawning, just like Neovim's LSP config
• Command availability check — Servers are silently skipped if the command isn't installed
• Multi-LSP support — Multiple LSPs can report diagnostics for the same file (e.g., TypeScript + Biome)
• Push & pull diagnostics — Supports both publishDiagnostics notifications and textDocument/diagnostic requests
• Footer status — Shows active LSP servers in the pi footer
• /lsp command — Lists all active LSP servers

Supported Languages

Language	LSP Server	Activation
TypeScript / JavaScript	typescript-language-server	tsconfig.json, jsconfig.json, or package.json
Python	pyright-langserver	pyproject.toml, setup.py, requirements.txt, Pipfile, pyrightconfig.json
Go	gopls	go.mod or go.work
C / C++	clangd	compile_commands.json, compile_flags.txt, .clangd, CMakeLists.txt, Makefile
Svelte	svelteserver	svelte.config.js/ts or svelte in package.json deps
CSS / SCSS / Less	vscode-css-language-server	package.json
HTML	vscode-html-language-server	package.json
JSON	vscode-json-language-server	package.json or .git
Biome (linter/formatter)	biome lsp-proxy	biome.json or biome.jsonc
Lua	lua-language-server	.luarc.json, .stylua.toml, selene.toml, etc.

Installation

pi install https://github.com/Huijiro/pi-lsp

Or add to your ~/.pi/agent/settings.json:

{
  "packages": [
    "https://github.com/Huijiro/pi-lsp"
  ]
}

Prerequisites

LSP servers must be installed separately. Only install the ones you need:

# TypeScript / JavaScript
npm install -g typescript-language-server typescript

# Python
npm install -g pyright

# Go
go install golang.org/x/tools/gopls@latest

# C / C++
# Install clangd via your system package manager

# Svelte
npm install -g svelte-language-server

# CSS / HTML / JSON
npm install -g vscode-langservers-extracted

# Biome
npm install -g @biomejs/biome

# Lua
# Install lua-language-server via your system package manager

Missing servers are silently skipped — you only need to install what you use.

Usage

Once installed, the extension works automatically:

• Read a file → diagnostics are appended if issues are found
• Use the diagnostics tool → the LLM can check any file on demand
• Run /lsp → see which LSP servers are active
• Check the footer → active LSPs are shown at the bottom

Contributing

Want to add a new LSP? See CONTRIBUTING.md.

License

MIT