claude-deno-lsp

claude-deno-lsp

A Claude Code plugin that provides Deno Language Server Protocol (LSP) integration for TypeScript/JavaScript code intelligence in Deno projects.

Prerequisites

• Deno installed and available in PATH
• Claude Code with LSP support

Verify Deno is installed:

deno --version

Installation

Add this plugin to your Claude Code configuration:

claude config add plugins /path/to/claude-deno

Or use --plugin-dir when starting Claude Code:

claude --plugin-dir /path/to/claude-deno

Features

The Deno LSP provides:

• Go to Definition - Jump to symbol definitions
• Hover Information - View type information and documentation
• Find References - Locate all usages of a symbol
• Document Symbols - List all symbols in a file
• Workspace Symbols - Search symbols across the project
• Diagnostics - Real-time error and lint warnings

Supported File Types

Extension	Language
.ts	TypeScript
.tsx	TypeScript React
.js	JavaScript
.jsx	JavaScript React
.mts, .cts	TypeScript (ESM/CJS)
.mjs, .cjs	JavaScript (ESM/CJS)

Usage

Once installed, the LSP tool becomes available for Deno files:

LSP goToDefinition <file> <line> <character>
LSP hover <file> <line> <character>
LSP findReferences <file> <line> <character>
LSP documentSymbol <file>

Limitations

No automatic workspace detection: Claude Code does not currently support rootPatterns for conditional LSP activation. This means:

• The Deno LSP activates for all supported file types when the plugin is enabled
• If you have other TypeScript LSP plugins enabled, there may be conflicts
• You should enable/disable this plugin manually when switching between Deno and Node projects

Workarounds:

1. Only enable this plugin when working on Deno projects
2. Disable TypeScript/Node LSP plugins when using Deno projects

Configuration

The LSP is configured with these initialization options:

Option	Value	Description
enable	true	Explicitly enable Deno language features
lint	true	Enable Deno's built-in linter
unstable	false	Disable unstable APIs by default

To customize these options, edit .lsp.json in the plugin directory.

Troubleshooting

LSP not starting

1. Verify Deno is installed: deno --version
2. Check that Deno is in your PATH
3. Ensure the plugin is properly loaded in Claude Code

Conflicts with other TypeScript LSPs

If you see duplicate diagnostics or conflicting suggestions:

1. Disable other TypeScript LSP plugins
2. Use only one LSP per file type

Unstable APIs not recognized

If you're using Deno unstable APIs, edit .lsp.json and set "unstable": true.

Resources

• Deno LSP Integration Docs
• Deno LSP CLI Reference
• Claude Code Plugins Reference

License

MIT