JsonDiffPatch MCP server

The diff-mcp server provides a powerful way to compare text or data and generate diffs in various formats. It's built on the jsondiffpatch library and can handle multiple input formats including JSON, YAML, TOML, XML, and HTML.

Features

• Text comparison using Google's diff-match-patch algorithm
• Data comparison (JSON, JSON5, YAML, TOML, XML, HTML)
• Multiple output formats (text, JSON, JSONPatch)

Installation

Install the diff-mcp server using npm:

npm install -g diff-mcp

Alternatively, you can run it without installation using npx:

npx diff-mcp

Usage

Setup with Claude Desktop

To integrate diff-mcp with Claude Desktop, add the following configuration to your claude_desktop_config.json file:

{
  "mcpServers": {
    "diff": {
      "command": "npx",
      "args": [
        "-y",
        "diff-mcp"
      ]
    }
  }
}

Using the Diff Tool

The diff tool accepts the following inputs:

• left: Left text or data (string, array, or object)
• leftFormat: Format of left input (optional, values: text, json, json5 (default), yaml, toml, xml, html)
• right: Right text or data to compare with left (string, array, or object)
• rightFormat: Format of right input (optional, values: text, json, json5 (default), yaml, toml, xml, html)
• outputFormat: Format for the diff output (optional, values: text (default), json, jsonpatch)

Example Usage

The server can be used to compare different types of content:

Comparing Text

{
  "left": "Hello world",
  "right": "Hello beautiful world",
  "leftFormat": "text",
  "rightFormat": "text",
  "outputFormat": "text"
}

Comparing JSON Data

{
  "left": {"name": "John", "age": 30},
  "right": {"name": "John", "age": 31},
  "outputFormat": "json"
}

Comparing YAML

{
  "left": "name: John\nage: 30",
  "right": "name: John\nage: 31",
  "leftFormat": "yaml",
  "rightFormat": "yaml",
  "outputFormat": "text"
}

Advanced Usage

You can use diff-mcp in combination with other tools or integrate it into your workflows to compare files, API responses, or any structured data that needs comparison.

How to install this MCP server

For Claude Code

To add this MCP server to Claude Code, run this command in your terminal:

claude mcp add-json "diff" '{"command":"npx","args":["-y","diff-mcp"]}'

See the official Claude Code MCP documentation for more details.

For Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > Tools & Integrations and click "New MCP Server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "diff": {
            "command": "npx",
            "args": [
                "-y",
                "diff-mcp"
            ]
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explicitly ask the agent to use the tool by mentioning the tool name and describing what the function does.

For Claude Desktop

To add this MCP server to Claude Desktop:

1. Find your configuration file:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/Claude/claude_desktop_config.json

2. Add this to your configuration file:

{
    "mcpServers": {
        "diff": {
            "command": "npx",
            "args": [
                "-y",
                "diff-mcp"
            ]
        }
    }
}

3. Restart Claude Desktop for the changes to take effect