How to try the ty type checker

This guide shows you how to try out ty, a static type checker and language server, in your project.

Prerequisites

To proceed, you’ll need uv.

Run ty from the command line

uvx ty check

This checks all Python files in the working directory or project.

Try ty online

ty has an online playground for trying it out on snippets or small projects. The playground is useful for sharing code examples with others.

Use the ty language server

ty includes a Language Server Protocol (LSP) implementation compatible with modern editors.

VS Code and Cursor

Install the official ty extension from the Visual Studio Marketplace.

Then disable the language server from the Python extension to avoid running two language servers. Add this to your settings.json:

{
  "python.languageServer": "None"
}

Neovim

For Neovim 0.10 or earlier with nvim-lspconfig:

require('lspconfig').ty.setup({
  settings = {
    ty = {
      -- ty language server settings go here
    }
  }
})

For Neovim 0.11+ with vim.lsp.config:

-- Optional: Only required if you need to update the language server settings
vim.lsp.config('ty', {
  settings = {
    ty = {
      -- ty language server settings go here
    }
  }
})

-- Required: Enable the language server
vim.lsp.enable('ty')

Zed

ty is included with Zed out of the box. Enable ty and disable basedpyright by adding this to your settings.json:

{
  "languages": {
    "Python": {
      "language_servers": ["ty", "!basedpyright", "..."]
    }
  }
}

PyCharm

Starting with version 2025.3, PyCharm has native ty support:

1. Go to Python | Tools | ty in the Settings dialog.
2. Select the Enable checkbox.
3. Choose an execution mode: Interpreter (uses ty from your interpreter) or Path (uses ty from $PATH).

Other editors

ty works with any editor that supports the Language Server Protocol. Start the language server with:

ty server

Refer to your editor’s documentation for connecting to an LSP server.