JADX (Java Decompiler) MCP server

The JADX-MCP-SERVER is a specialized Python server that bridges the JADX decompiler with Large Language Models (LLMs) like Claude through the Model Context Protocol (MCP). This server allows you to analyze Android APKs using AI, helping with vulnerability detection, manifest parsing, and reverse engineering tasks.

Installation

Prerequisites

• Python 3.10 or higher
• Java 11 or higher
• JADX-AI-MCP plugin installed

Setup

To get started with JADX-MCP-SERVER, download the latest release from the official repository:

https://github.com/zinja-coder/jadx-ai-mcp/releases

Usage

Running the Server

After downloading and setting up the MCP server, you'll need to connect it to the JADX-AI-MCP plugin to begin analyzing Android APKs.

Available MCP Tools

The server provides several powerful tools for reverse engineering and code analysis:

• Code Analysis Tools:

  • fetch_current_class() - Retrieves the class name and full source of selected class
  • get_selected_text() - Gets currently selected text
  • get_all_classes() - Lists all classes in the project
  • get_class_source() - Gets full source of a given class
  • get_method_by_name() - Fetches a method's source
  • search_method_by_name() - Searches method across classes
  • get_methods_of_class() - Lists methods in a class
  • get_fields_of_class() - Lists fields in a class
  • get_smali_of_class() - Fetches smali of class

• Android App Analysis Tools:

  • get_main_activity_class() - Fetches main activity from AndroidManifest.xml
  • get_main_application_classes_code() - Fetches all main application classes' code
  • get_main_application_classes_names() - Fetches all main application classes' names
  • get_android_manifest() - Retrieves AndroidManifest.xml content
  • get_strings() - Fetches the strings.xml file
  • get_all_resource_file_names() - Retrieves all resource files names
  • get_resource_file() - Retrieves resource file content

Using with Ollama (Local LLM)

For those wanting to run analysis using local LLMs, you can use the Zin MCP Client which provides a bridge between Ollama-based LLMs and MCP servers.

Example Prompts

Basic Code Understanding

"Explain what this class does in one paragraph."
"Summarize the responsibilities of this method."
"Is there any obfuscation in this class?"
"List all Android permissions this class might require."

Vulnerability Detection

"Are there any insecure API usages in this method?"
"Check this class for hardcoded secrets or credentials."
"Does this method sanitize user input before using it?"
"What security vulnerabilities might be introduced by this code?"

Reverse Engineering Helpers

"Deobfuscate and rename the classes and methods to something readable."
"Can you infer the original purpose of this smali method?"
"What libraries or SDKs does this class appear to be part of?"

Static Analysis

"List all network-related API calls in this class."
"Identify file I/O operations and their potential risks."
"Does this method leak device info or PII?"

AI Code Modification

"Refactor this method to improve readability."
"Add comments to this code explaining each step."
"Rewrite this Java method in Python for analysis."

Documentation & Metadata

"Generate Javadoc-style comments for all methods."
"What package or app component does this class likely belong to?"
"Can you identify the Android component type (Activity, Service, etc.)?"

Related Tools

The JADX-MCP-SERVER is part of the Zin MCP Suite, which includes:

• APKTool-MCP-Server
• JADX-AI-MCP-Plugin
• ZIN-MCP-Client

How to add this MCP server to 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 > MCP and click "Add new global MCP server".

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

{
    "mcpServers": {
        "cursor-rules-mcp": {
            "command": "npx",
            "args": [
                "-y",
                "cursor-rules-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 explictly ask the agent to use the tool by mentioning the tool name and describing what the function does.