RayenMalouche/MCP-Fetch-Server-Java-version

MCP Fetch Server - Java Implementation

A Java-based Model Context Protocol (MCP) server that provides web content fetching and conversion capabilities. This is a Java port of the original TypeScript MCP fetch server.

Features

The server provides four main tools for web content processing:

1. get_raw_text: Retrieves raw text content directly from URLs without browser rendering
2. get_rendered_html: Fetches fully rendered HTML content using Playwright browser automation
3. get_markdown: Converts web page content to well-formatted Markdown
4. get_markdown_summary: Extracts main content area and converts to Markdown (removes navigation, headers, footers)

Project Structure

src/main/java/com/mcp/RayenMalouche/java/server/Fetch/
├── FetchApplication.java               # Main application class
├── service/
│   └── WebContentService.java         # Core web content processing service
└── tools/
│   ├── BaseFetchTool.java              # Base class for all fetch tools
│   ├── GetRawTextTool.java             # Raw text fetching tool
│   ├── GetRenderedHtmlTool.java        # HTML rendering tool
│   ├── GetMarkdownTool.java            # Markdown conversion tool
│   └── GetMarkdownSummaryTool.java     # Main content extraction tool
└── controller/
    └── WebContentController.java       # REST Controller

Prerequisites

• Java 17 or higher
• Maven 3.6 or higher
• Internet connection (for downloading Playwright browsers)

Installation

1. Clone the repository:

git clone https://github.com/RayenMalouche/MCP-Fetch-Server-Java-version
cd MCP-Fetch-Server-Java-version

2. Install Playwright browsers (required for rendered HTML functionality):

For windows:

# Save the install-playwright.bat script and run it
install-playwright.bat

# Or manually
mvn exec:java -Dexec.mainClass="com.microsoft.playwright.CLI" -Dexec.args="install"

3. Build the project:

mvn clean compile

4. Package the application:

mvn package

Running the Server

Development Mode

mvn spring-boot:run

Production Mode

java -jar target/Fetch-0.0.1-SNAPSHOT.jar

The server will start on port 45455 by default.

Configuration

You can modify the server configuration by editing the following constants in FetchApplication.java:

• SERVER_PORT: Change the port number (default: 45455)
• SERVER_NAME: Modify the server name
• SERVER_VERSION: Update the version string

API Endpoints

The server exposes the following MCP tools via HTTP Server-Sent Events (SSE):

get_raw_text

{
  "name": "get_raw_text",
  "arguments": {
    "url": "https://example.com/data.json"
  }
}

get_rendered_html

{
  "name": "get_rendered_html",
  "arguments": {
    "url": "https://example.com"
  }
}

get_markdown

{
  "name": "get_markdown",
  "arguments": {
    "url": "https://example.com/article"
  }
}

get_markdown_summary

{
  "name": "get_markdown_summary",
  "arguments": {
    "url": "https://example.com/blog-post"
  }
}

Dependencies

Core Dependencies

• Spring Boot: Application framework
• MCP SDK: Model Context Protocol implementation
• Jackson: JSON processing
• Jetty: HTTP server

Web Processing

• Playwright: Browser automation for rendered content
• JSoup: HTML parsing and manipulation
• Flexmark: HTML to Markdown conversion
• Java HTTP Client: Raw content fetching

Error Handling

The server includes comprehensive error handling for:

• Invalid URLs
• Network timeouts
• Browser automation failures
• HTML parsing errors
• Markdown conversion issues

All errors are returned as MCP tool results with descriptive error messages.

Performance Considerations

• Raw text fetching: Fast, direct HTTP requests
• Rendered HTML: Slower due to browser automation overhead
• Markdown conversion: Additional processing time for HTML parsing
• Browser resources: Playwright browsers are properly cleaned up after use

Testing

Run the test suite:

mvn test

Troubleshooting

Playwright Issues

If you encounter Playwright browser issues:

mvn exec:java@install-playwright-browsers

or force reinstall:

mvn exec:java -Dexec.mainClass="com.microsoft.playwright.CLI" -Dexec.args="install --force"

Memory Issues

For large pages, increase JVM memory:

java -Xmx2g -jar target/Fetch-0.0.1-SNAPSHOT.jar

Port Conflicts

Change the port in FetchApplication.java if 45455 is already in use.

License

MIT License - See the original TypeScript implementation for details.

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Add tests
5. Submit a pull request

Acknowledgments

This project is a Java port of the original TypeScript implementation by tatn.