pubdev_mcp_bridge

AI assistants hallucinate Dart APIs. This fixes it.

pubdev_mcp_bridge serve dio

Extracts accurate API documentation from any pub.dev package and serves it via MCP, giving AI assistants like Claude, Cursor, and Windsurf perfect knowledge of Dart libraries.

Why This Matters

• Any package: Works with all public packages on pub.dev
• Any MCP client: Compatible with Claude Code, Claude Desktop, Cursor, Windsurf, Cline, and other MCP-enabled tools
• Zero configuration: One command to extract and serve documentation
• Always accurate: Extracts documentation directly from source code using the Dart analyzer
• Experimental features: Supports packages using macros, records, dot-shorthands, and other modern Dart syntax

Installation

Prerequisites: Dart SDK 3.7.0 or later

Install globally from pub.dev:

dart pub global activate pubdev_mcp_bridge

Make sure the pub cache bin directory is in your PATH:

• macOS/Linux: Add export PATH="$PATH":"$HOME/.pub-cache/bin" to your shell profile
• Windows: Add %LOCALAPPDATA%\Pub\Cache\bin to your PATH

Or install from source:

git clone https://github.com/heyaphra/pubdev_mcp_bridge.git
cd pubdev_mcp_bridge
dart pub get
dart pub global activate --source path .

Usage

serve <package> - Start MCP Server

Extracts documentation (if not cached) and starts an MCP server:

# Serve the latest version
pubdev_mcp_bridge serve riverpod

# Serve a specific version
pubdev_mcp_bridge serve riverpod --version 2.5.0

# Force re-extraction (ignore cache)
pubdev_mcp_bridge serve riverpod --refresh

extract <package> - Extract Documentation Only

Downloads and extracts documentation without starting a server:

pubdev_mcp_bridge extract freezed
pubdev_mcp_bridge extract freezed --version 2.4.0

list - List Cached Packages

Shows all packages with cached documentation:

pubdev_mcp_bridge list
# Output:
# Cached packages:
#   riverpod@2.6.1
#   dio@5.4.0
#   music_notes@0.24.0

clean - Remove Cached Data

# Remove a specific package (all versions)
pubdev_mcp_bridge clean riverpod

# Remove a specific version
pubdev_mcp_bridge clean riverpod --version 2.5.0

# Remove all cached data
pubdev_mcp_bridge clean --all

Connecting to AI Assistants

Claude Code

Use the claude mcp add command:

# Add a server (if installed globally)
claude mcp add riverpod pubdev_mcp_bridge serve riverpod

# Or run directly from the project directory
claude mcp add riverpod dart run /path/to/pubdev_mcp_bridge/bin/pubdev_mcp_bridge.dart serve riverpod

Scope options:

# Add to current project only
claude mcp add --scope project riverpod pubdev_mcp_bridge serve riverpod

# Add globally (available in all projects)
claude mcp add --scope user riverpod pubdev_mcp_bridge serve riverpod

Verify registration:

claude mcp list

Claude Desktop

Add the server to your Claude Desktop configuration (claude_desktop_config.json):

{
  "mcpServers": {
    "riverpod": {
      "command": "pubdev_mcp_bridge",
      "args": ["serve", "riverpod"]
    }
  }
}

Or if not installed globally:

{
  "mcpServers": {
    "riverpod": {
      "command": "dart",
      "args": ["run", "/path/to/pubdev_mcp_bridge/bin/pubdev_mcp_bridge.dart", "serve", "riverpod"]
    }
  }
}

Cursor / Windsurf

Add to your MCP settings file (location varies by editor):

{
  "mcpServers": {
    "dio": {
      "command": "pubdev_mcp_bridge",
      "args": ["serve", "dio"]
    }
  }
}

Other MCP Clients

Any tool that supports the Model Context Protocol can connect to pubdev_mcp_bridge. Consult your tool's documentation for MCP server configuration.

Available Tools

Tool	Description
search	Search documentation by keyword
get_class	Get detailed class documentation
get_function	Get function documentation
get_enum	Get enum documentation
get_library	Get library overview
get_methods	List all methods of a class
list_classes	List all classes in the package
list_functions	List all top-level functions
list_enums	List all enums
list_libraries	List all libraries
get_package_info	Get package metadata and statistics

Example: Accurate API Responses

With the music_notes package server running, AI assistants can answer questions with perfect accuracy:

User: "How do I create a chord in the music_notes package?"

AI Assistant (with pubdev_mcp_bridge):

You can create a Chord using its constructor:

  Chord(this._items)

The Chord class is generic (Chord<T>) and implements Transposable<Chord<T>>.

Example usage:
  final chord = Chord([Note.c, Note.e, Note.g]);
  
You can also get the chord's pattern:
  ChordPattern pattern = chord.pattern();

Or transpose it:
  Chord<T> transposed = chord.transposeBy(Interval.perfectFourth);

Without pubdev_mcp_bridge: Hallucinated APIs, outdated examples, incorrect method signatures.

How It Works

┌─────────────┐     ┌─────────────┐     ┌─────────────┐
│   pub.dev   │────▶│  Extractor  │────▶│    Cache    │
│   (HTTP)    │     │  Pipeline   │     │   (JSON)    │
└─────────────┘     └─────────────┘     └─────────────┘
                                               │
                                               ▼
                    ┌─────────────┐     ┌─────────────┐
                    │     AI      │◀────│ MCP Server  │
                    │  Assistant  │     │  (stdio)    │
                    └─────────────┘     └─────────────┘

pubdev_mcp_bridge downloads packages from pub.dev, extracts API documentation using the Dart analyzer, caches it locally as JSON, and serves it via an MCP server. AI assistants query the server to get accurate, up-to-date information about Dart packages.

Limitations

• Path dependencies: Packages with path dependencies (e.g., path: ../sibling_package in monorepos) will fail during dart pub get because the sibling packages don't exist in the extracted directory. Try a different version or contact the package maintainer.
• Private packages: Only public packages on pub.dev are supported. The tool uses unauthenticated HTTP requests to the pub.dev API.
• SDK constraints: Packages requiring a newer Dart SDK than you have installed will fail during dart pub get. For example, if a package requires sdk: ^3.8.0 but you have Dart 3.7.0, extraction will fail. Upgrade your Dart SDK or try an older package version.

Troubleshooting

Server starts but tools don't appear

Restart your AI assistant or IDE. Some clients cache MCP server capabilities.

Extraction fails for a specific package

Try a different version:

pubdev_mcp_bridge serve package_name --version 1.2.3

Cache issues

Clear the cache and re-extract:

pubdev_mcp_bridge clean --all
pubdev_mcp_bridge serve package_name --refresh

Check cached documentation

# List cached packages
ls ~/.pubdev_mcp_cache/docs/

# View cached JSON
cat ~/.pubdev_mcp_cache/docs/dio-5.4.0.json | head -100

Windows users: Replace ~/.pubdev_mcp_cache with %LOCALAPPDATA%\pubdev_mcp_cache

Contributing

Contributions are welcome! See CONTRIBUTING.md for development setup, architecture details, and guidelines.

License

MIT License - see LICENSE file for details.

Acknowledgments

• Built with dart_mcp from the Dart team
• Extraction powered by analyzer from the Dart team
• Model Context Protocol by Anthropic