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# Zed

The BAML extension for [Zed](https://zed.dev) provides syntax highlighting and language server support for editing BAML files.

## Installation

1. Open Zed
2. Open the Extensions panel: **Zed** → **Extensions** (or press `Cmd+Shift+X` on macOS)
3. Search for "**baml**"
4. Click **Install**

The extension will automatically download and configure the BAML language server.

## Features

| Feature                                    | Supported |
| ------------------------------------------ | --------- |
| Syntax highlighting for BAML files         | ✅         |
| Language Server Protocol (LSP) integration | ✅         |
| Jump to definition                         | ✅         |
| Error diagnostics                          | ✅         |
| LLM playground (via browser)               | ✅         |

## Opening the BAML Playground

The BAML Playground runs as a local server and can be accessed via your browser:

1. Open the Command Palette with `Cmd+Shift+P` (macOS) or `Ctrl+Shift+P` (Linux)
2. Search for "**open language server logs**" and select **dev: open language server logs**
3. In the LSP Logs panel, search for "**Starting Playground server on**"
4. Copy the URL shown (e.g., `127.0.0.1:3704`)
5. Open that URL in your browser to access the playground

> **Tip**
>
> The playground server starts automatically when the BAML language server initializes. If you don't see the message, try restarting the language server.

> **Note**
>
> **Why can't I just click "Open Playground" like in VS Code?**
>
> In VS Code, Cursor, and JetBrains, you'll see an "Open Playground" button above each BAML function. Unfortunately, Zed doesn't yet support the LSP features needed to make this work:
>
> * [Code Lens](https://github.com/zed-industries/zed/issues/11565) — the inline buttons above functions
> * [workspace/executeCommand](https://github.com/zed-industries/zed/issues/13756) — executing editor commands from LSP
>
> Once Zed adds these features, the playground will be accessible with a single click. Until then, the LSP logs workaround above is the way to go. You can follow the linked GitHub issues to track progress.

## How It Works

The Zed extension includes:

* **Tree-sitter grammar**: Provides accurate syntax highlighting based on the [BAML tree-sitter grammar](https://github.com/BoundaryML/tree-sitter-baml)
* **Language Server**: Connects to the BAML Language Server for features like jump-to-definition, diagnostics, and more

## Setting Environment Variables

You can set environment variables (like API keys) in the BAML Playground via your browser. Click on the **Settings** button in the playground to configure them.

Alternatively, you can set environment variables in your shell or through a `.env` file in your project root. The BAML language server will pick up variables from your environment.

> **Info**
>
> Environment variables set in the playground are stored locally and persist between sessions.

## Troubleshooting

### Extension not appearing

Make sure you're running a recent version of Zed. The BAML extension requires Zed's extension system.

### Language Server not starting

If the language server fails to start:

1. Check the Zed logs for errors
2. Make sure you have an internet connection (the extension downloads the language server on first use)
3. Try reinstalling the extension

### Syntax highlighting not working

Ensure your files have the `.baml` extension. The extension only activates for files with this extension.

## Source Code

The Zed extension is developed as part of the BAML monorepo:

* Extension source: [github.com/BoundaryML/baml](https://github.com/BoundaryML/baml/tree/canary/engine/zed)
* Tree-sitter grammar: [github.com/BoundaryML/tree-sitter-baml](https://github.com/BoundaryML/tree-sitter-baml)

## Feedback

If you encounter any issues or have feature requests, please:

* Open an issue on [GitHub](https://github.com/BoundaryML/baml)
* Join our [Discord](https://discord.gg/BTNBeXGuaS) for support