MCP Edit Service

A Model Context Protocol (MCP) server that provides file editing capabilities using Morph's fast apply API.

Features

• Edit files using natural language instructions
• Powered by Morph's LLM (configurable model)
• Automatic backup creation before edits
• Graceful error handling for file I/O and API errors
• MCP-compatible for use with AI IDEs

Setup

1. Install dependencies:

npm install

2. Set your Morph API key:

export MORPH_API_KEY=your_api_key_here

3. (Optional) Set custom API base URL:

export MORPH_BASE_URL=https://your-custom-api.com/v1

If not set, defaults to https://api.morphllm.com/v1

4. (Optional) Set custom model:

export MORPH_MODEL=your-preferred-model

If not set, defaults to morph/morph-v3-large

5. Build the project:

npm run build

Usage in MCP-compatible AI IDEs

Claude Desktop

Add this to your claude_desktop_config.json:

{
  "mcpServers": {
    "edit-service": {
      "command": "node",
      "args": ["/path/to/mcp-edit-service/dist/index.js"],
      "env": {
        "MORPH_API_KEY": "your_api_key_here",
        "MORPH_BASE_URL": "https://your-custom-api.com/v1",
        "MORPH_MODEL": "your-preferred-model"
      }
    }
  }
}

Cursor or other MCP-compatible IDEs

Configure the MCP server with:

• Command: node /path/to/mcp-edit-service/dist/index.js
• Environment:
  • MORPH_API_KEY=your_api_key_here
  • MORPH_BASE_URL=https://your-custom-api.com/v1 (optional)
  • MORPH_MODEL=your-preferred-model (optional)

Available Tools

edit_file

Edits an existing file using Morph's fast apply API.

Parameters:

• target_file (string, required): Path to the file to edit
• instructions (string, required): Single sentence describing the edit
• code_edit (string, required): Only the lines to change with // ... existing code ... comments for unchanged sections

Example:

{
  "target_file": "src/main.js",
  "instructions": "Add error handling to the fetch function",
  "code_edit": "try {\n  const response = await fetch(url);\n  // ... existing code ...\n} catch (error) {\n  console.error('Fetch failed:', error);\n  throw error;\n}"
}

Development

# Development mode
npm run dev

# Build
npm run build

# Start production server
npm start

Error Handling

The service provides comprehensive error handling for:

• Missing or invalid API keys
• File access permissions
• Network errors with Morph API
• Invalid tool arguments
• File I/O operations

All errors are returned in a structured JSON format with descriptive messages.