LSP Module

LSP Module

Purpose

Implements a minimal Language Server Protocol client to fetch diagnostic feedback (errors, warnings) from language servers.

Key Components

client.py

LSPClient Class Main LSP client implementation:

• start_server() - Spawn language server process
• initialize() - Initialize LSP handshake
• get_diagnostics() - Fetch diagnostics for file
• shutdown() - Gracefully terminate server
• did_open() - Notify file open
• did_change() - Notify file change
• did_close() - Notify file close

Features:

• Async subprocess management
• JSON-RPC communication
• Server lifecycle management
• Error handling and recovery

diagnostics.py

Diagnostic Functions:

• get_diagnostics() - Fetch diagnostics for file
• format_diagnostics() - Format for display
• parse_diagnostics() - Parse LSP response

Diagnostic Types:

• Error - Critical issues
• Warning - Potential problems
• Information - Suggestions
• Hint - Style recommendations

servers.py

Language Server Registry Supported language servers:

• Python - pylsp, python-lsp-server
• JavaScript/TypeScript - typescript-language-server
• Go - gopls
• Rust - rust-analyzer
• etc.

Server Configuration:

{
  "language": "python",
  "command": "pylsp",
  "args": [],
  "workspace": Path
}

LSP Workflow

1. Start server process
2. Initialize LSP handshake
3. Notify file open (did_open)
4. Get diagnostics
5. Notify file change (did_change)
6. Get updated diagnostics
7. Notify file close (did_close)
8. Shutdown server

Integration Points

• tools/write_file.py - Trigger diagnostics after write
• tools/update_file.py - Trigger diagnostics after update
• tools/decorators.py - LSP integration in file_tool decorator
• ui/renderers/tools/diagnostics.py - Display diagnostics

Usage

Tool decorator integration:

@file_tool(writes=True)
async def write_file(filepath: str, content: str):
    # Write file
    ...
    # Fetch diagnostics
    diagnostics = await lsp_client.get_diagnostics(filepath)
    # Append to output
    return result + diagnostics

Seams (M, D)

Modification Points:

• Add new language servers
• Customize LSP client behavior
• Extend diagnostic formatting
• Add LSP features (completion, hover, etc.)

Extension Points:

• Implement additional LSP capabilities
• Add server auto-detection
• Create custom diagnostic formatters
• Add LSP server management