Android Source Explorer MCP Server

MCP server for exploring AOSP internals and Jetpack libraries.

Purpose

When building Android applications, AI tools often rely on outdated training data or incomplete summaries of the Android Framework. This MCP server provides on-demand, precise access to the actual source code (AOSP and AndroidX), enabling the AI to understand complex framework internals like the Activity lifecycle, ViewModel restoration, or Compose internals directly from the truth.

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Installation & Setup

Prerequisites

• uv (Recommended) or Python 3.11+
• Git

Recommended Installation (via uv)

The easiest way to install and keep android-source-explorer up to date is using uv. It handles dependencies (including native ones like Tree-sitter and Cryptography) reliably across platforms.

uv tool install git+https://github.com/mrmike/android-source-explorer-mcp

This will make the android-source-explorer command available globally in your PATH.

Initial Sync

After installation, you need to perform an initial sync to fetch the Android source code:

# Sync API 36 (Android 16) and common AndroidX packages
android-source-explorer sync --api-level 36 --androidx "compose,lifecycle,activity"

# (Optional) Download LSP servers for cross-file features
android-source-explorer sync --lsp

Check sync status:

android-source-explorer status

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Configuration

Add the MCP server to your configuration file (e.g., Claude Desktop, Cursor, Gemini CLI).

Global Usage (Recommended)

If installed via uv tool install, the tool is available globally.

Basic Setup:

{
  "mcpServers": {
    "android-sources": {
      "command": "android-source-explorer",
      "args": ["serve"]
    }
  }
}

With LSP Features Enabled:

{
  "mcpServers": {
    "android-sources": {
      "command": "android-source-explorer",
      "args": ["serve"],
      "env": {
        "ANDROID_SOURCE_LSP": "true"
      }
    }
  }
}

Development Usage

If you cloned the repository and want to run it from the source:

{
  "mcpServers": {
    "android-sources": {
      "command": "uv",
      "args": ["run", "--directory", "/absolute/path/to/android-source-explorer", "android-source-explorer", "serve"]
    }
  }
}

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How It Works

1. Hybrid Architecture (Tree-sitter + LSP)

The server uses a dual-engine approach to balance speed and intelligence:

• Tree-sitter (Surgical Engine): Provides near-instant (sub-10ms) AST parsing of single files. It precisely extracts method bodies (including Javadoc and annotations), class members, and inheritance hierarchies without the overhead of a full compiler.
• LSP (Global Engine): Optionally leverages the Eclipse JDT LS (Java) and Kotlin Language Server for cross-file navigation. This enables finding references across millions of lines of code and resolving types that span multiple libraries.

2. Local Sync Strategy

To ensure all lookups are instant and offline-ready, the server uses a sync command to pre-fetch sources into a local cache (~/.android-sources/):

• AOSP: Fetches framework sources directly from android.googlesource.com using git sparse-checkouts.
• AndroidX: Downloads -sources.jar files from the Google Maven repository (dl.google.com/dl/android/maven2/).
• Hybrid Indexing: Prioritizes your local $ANDROID_HOME sources if available, supplemented by the downloaded cache.

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Available Tools

Tool	Engine	Description
search_classes	Index	Search for classes by glob pattern or substring.
lookup_class	FS	Retrieve the full source code for a specific class.
lookup_method	Tree-sitter	Extract a precise method body + its Javadoc/annotations.
list_class_members	Tree-sitter	List all method and field signatures in a class.
get_class_hierarchy	Tree-sitter	Get the inheritance chain (superclass + interfaces).
search_in_source	FS/Regex	Search for text/regex across the entire source tree.
goto_definition*	LSP	Resolve the cross-file definition of a symbol.
find_references*	LSP	Find all usages of a class/method across the whole tree.
get_type_info*	LSP	Get documentation and type info via hover data.

*Requires ANDROID_SOURCE_LSP=true

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License

Apache License 2.0