> ## Documentation Index
> Fetch the complete documentation index at: https://onr.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# ONR Language Server (LSP)

> Rich DSL IDE support for VSCode & Neovim.

The `onr-lsp` provides advanced IDE capabilities for editing Open Next Router DSL config files, including provider files, reusable mode preset files, and merged/root config entrypoints such as `onr.conf` and `providers.conf`. It is distributed both as a standalone Language Server binary and a packaged VS Code extension.

## Feature Highlights

* **Syntax Highlighting**: Immediate TextMate lexical parsing paired with semantic token coloring from the language server.
* **Intelligent Autocomplete**: Provides directive completion dynamically depending on the current DSL block, built-in mode suggestions for directives like `req_map`, `resp_map`, and `sse_parse`, and enum value suggestions such as `balance_unit` and `method`.
* **Preset-Aware Completion**: Suggests user-defined top-level preset names for `usage_extract`, `finish_reason_extract`, `models_mode`, and `balance_mode`.
* **Hover Documentation**: Short documentation tooltips injected directly from the ONR DSL metadata definitions.
* **Diagnostics**: Real-time syntax validation (missing braces, unknown directives) and semantic checks.
* **Auto Formatting**: Leverages `textDocument/formatting` to keep your `.conf` files neat and standardized.

## Installation

### VS Code Extension

You can find the official [Open Next Router DSL](https://marketplace.visualstudio.com/items?itemName=r9s-ai.onr-dsl) extension in the VS Code Marketplace.

Once installed, the language server will automatically activate for:

* `**/providers/*.conf`
* `**/modes/*.conf`
* `**/onr.conf`
* `**/providers.conf`

### Default Settings

The extension applies the following default editor settings for ONR DSL files:

```json theme={null}
"[onr-dsl]": {
    "editor.defaultFormatter": "r9s-ai.onr-dsl",
    "editor.formatOnSave": true
}
```

If you prefer to use a custom LSP path over the bundled binary, you can set `onrLsp.serverPath` in your workspace settings wrapper.

***

## Standalone CLI Formatter

Aside from the LSP, the binary also functions as a powerful command-line formatter.

```bash theme={null}
# Build the LSP binary manually
go build -o bin/onr-lsp ./cmd/onr-lsp

# Read from stdin, write formatted result to stdout
cat config/providers/openai.conf | ./bin/onr-lsp format

# Format a specific file and output to stdout
./bin/onr-lsp format config/providers/openai.conf

# Format one file in-place
./bin/onr-lsp format --write config/providers/openai.conf
```