dart-pubdev-explorer #

Ships as the dart_pubdev_mcp package on pub.flutter-io.cn; the server and CLI identify themselves as dart-pubdev-explorer.

A Model Context Protocol server that gives AI coding agents structured, version-aware access to the pub.flutter-io.cn Dart and Flutter package registry. Instead of scraping HTML, guessing package names, or repeating stale advice from training data, an agent can search, compare, and read packages — down to an exact source line — the way a careful maintainer would.

Why it exists #

Agents without this server tend to guess package names, hallucinate APIs, or paste in stale advice from training data. dart-pubdev-explorer backs every answer with a live call to pub.flutter-io.cn, dartdoc, or the package tarball itself, so an agent's answer is grounded instead of guessed.

Features #

• Find the right package. search_packages ranks by relevance, likes, pub points, or recency, filtered by SDK and platform.
• Read the real docs. Full READMEs, examples, changelogs, and pubspec.yaml, fetched at the exact version being targeted.
• Browse the API like a human would. Search a package's public symbols by name or keyword, then read full signatures, doc comments, and every throw site.
• Read exact source. Pull a file by line range or by symbol name — resolved through the analyzer AST — without downloading and unpacking a tarball by hand.
• Compare candidates side by side. Score, platform support, and maintenance signals for 2–5 packages in one call.
• Plan upgrades with confidence. Structured changelog entries flagged breaking, plus a symbol-level diff between any two versions.

Quick start #

1. Install #

Requires the Dart SDK (>=3.9.0).

dart install dart_pubdev_mcp

This installs the dart-pubdev-explorer executable onto your PATH. Verify with:

dart-pubdev-explorer --version

To upgrade later, re-run dart install dart_pubdev_mcp (add --overwrite if another package has already claimed the dart-pubdev-explorer executable name).

2. Configure your MCP client #

Add a stdio server entry pointing at the installed executable. For example, in Claude Code / Claude Desktop's .mcp.json:

{
  "mcpServers": {
    "dart-pubdev-explorer": {
      "command": "dart-pubdev-explorer"
    }
  }
}

Any MCP client that speaks stdio works the same way — Cursor, Windsurf, Zed, and others follow the same shape, a bare command with no arguments required. Pass any of the CLI flags below in args if you need non-default behavior.

3. Try it #

Once connected, ask your agent something that needs live package data instead of training-data guesses, for example:

"Compare dio and http for a Flutter app that needs file uploads — which has better platform support and is more actively maintained?"

The agent resolves this itself: search_packages to confirm both names exist, compare_packages for the side-by-side score/platform/maintenance matrix, then get_symbol_documentation if it needs to check a specific API before recommending one.

Tools #

All tools return JSON. Every tool that accepts a package version omits it to resolve the latest stable release, and the response then carries a resolvedVersion field naming what was actually used.

Errors from any tool carry a machine-readable code and a suggestion field describing the next step (e.g. AMBIGUOUS_SYMBOL includes candidate qualified names to retry with).

Typical flows #

• Discovery: search_packages → get_package → the readme resource for full setup docs.
• API exploration: get_symbol_documentation directly if the symbol name is known, otherwise browse_api_symbols first → get_throw_statements → get_source_slice if more implementation detail is needed.
• Upgrade analysis: get_changelog with from_version set → check breaking flags → get_api_diff for the precise symbol-level delta.
• Choosing between packages: search_packages → compare_packages on the top candidates.

Resources #

In addition to tools, the server exposes read-only MCP resources. Read pub://meta/resources first to get the full manifest as JSON.

Package resource URIs require an explicit @{version} segment; use @latest to resolve the latest stable release.

Configuration #

All settings are optional; CLI flags take precedence over environment variables, which take precedence over defaults.

Run dart-pubdev-explorer --help for the same reference from the CLI, or dart-pubdev-explorer --version to print the installed version.

How this compares #

The official Dart MCP server (dart mcp-server) ships a general pub_dev_search tool alongside its much broader Dart/Flutter tooling surface — running apps, analysis, DTD, and more. dart-pubdev-explorer is a focused, deeper tool for package research specifically: symbol-level API browsing, exact source reads, multi-version diffing, and side-by-side comparison, backed by an on-disk cache tuned for the repeated lookups a single research session tends to make. The two are complementary — run both.

Contributing #

Source, issues, and the changelog live in the agentic_dart monorepo, under packages/dart_pubdev_mcp. Bug reports and pull requests are welcome via the issue tracker.

License #

MIT License — see LICENSE.