LABSCO SUMMARY

The dependency question gets answered before the install, not by the install failing.

check_package_python_compatibility and resolve_dependencies answer the two things a lockfile only tells you after the fact: whether the package accepts your interpreter, and what the tree actually pulls in at a given depth with extras on or off. download_package then writes that resolved set to a directory with checksums verified, which is the piece that makes an air-gapped install possible. Nothing here installs into an environment or edits a requirements file — the server reads the index and writes files to a path you name.

What it is

A query layer over PyPI covering package metadata, Python-version compatibility, recursive dependency resolution, bulk download and download statistics.

What you get

Package metadata, the full version list with release details and distribution formats, and dependencies for a named version or the latest
A compatibility verdict for a package against a target Python version, and the reverse — which Python versions a package accepts, with recommendations
Recursive dependency resolution across the whole tree, with switches for target Python version, extras, dev dependencies and maximum depth
Download of a package and its resolved dependencies into a local directory, wheel-preferred, with checksum verification
Download counts for a day, week or month, a 180-day trend series with or without mirrors, and the current most-downloaded list

Requirements

Reachable package index. Four environment variables are read — PYPI_INDEX_URL and PYPI_INDEX_URLS to point at an index other than the default, PYPI_CACHE_TTL and PYPI_LOG_LEVEL — and no account or token is configured for any of them.

Setup effort

One command — uvx pypi-query-mcp-server

See installation options

USE CASES

01

Clearing a package for the Python version you are actually running

Check the package against your target interpreter, and when it fails, ask which versions it does accept before you decide whether to move the project or the dependency.

check_package_python_compatibilityget_package_compatible_python_versionsget_package_versions

02

Seeing what a new dependency drags in before you add it

Resolve the tree to the depth you care about with extras and dev dependencies switched on or off, and read the direct requirements for a specific version rather than the latest.

resolve_dependenciesget_package_dependenciesget_package_info

03

Staging a build for a machine with no route to the internet

Resolve the tree for the target interpreter, then download the package and everything it needs into a directory, preferring wheels and verifying checksums as it goes.

resolve_dependenciesdownload_package

04

Choosing between two libraries that claim to do the same thing

Compare recent download counts over a chosen period and the 180-day trend, and check where each sits against the most-downloaded list.

get_download_statisticsget_download_trendsget_top_downloaded_packages

10 tools

Counted once with only startup setup. Other versions, modes or optional credentials may expose a different list.

`check_package_python_compatibility`

Check if a package is compatible with a specific Python version.

This tool analyzes a package's Python version requirements and determines if it's compatible with your target Python version.

Args: package_name: The name of the PyPI package to check (e.g., 'django', 'requests') target_python_version: Target Python version to check (e.g., '3.9', '3.10.5', '3.11') use_cache: Whether to use cached package data (default: True)

Returns: Dictionary containing detailed compatibility information including:

Compatibility status (True/False)
Source of compatibility information (requires_python or classifiers)
Detailed analysis and suggestions
Package version requirements

Raises: InvalidPackageNameError: If package name is empty or invalid PackageNotFoundError: If package is not found on PyPI NetworkError: For network-related errors

BEFORE YOU INSTALL

What to know first

Tools you get

10 tools when we connected. The documentation numbers 24 entries, but items 11-24 are prompt templates, not tools. Private repository support is still planned, although its environment variables are already documented.

CONTEXT COST

Light Standing cost

Rated by the size of the 10 tool definitions that ride along on every turn, not by how many there are

INSTALLATION

Connect your client

Server setup

TERMINAL

uvx pypi-query-mcp-server

MCP Clients

Claude Code

CLAUDE CODE · TERMINAL

claude mcp add pypi uvx pypi-query-mcp-server -s local

Claude Desktop

CLAUDE DESKTOP · JSON

{
  "mcpServers": {
    "pypi-query": {
      "command": "uvx",
      "args": [
        "--from",
        "pypi-query-mcp-server",
        "pypi-query-mcp"
      ],
      "env": {
        "PYPI_INDEX_URL": "https://pypi.org/pypi",
        "PYPI_INDEX_URLS": "https://mirrors.aliyun.com/pypi/simple/,https://pypi.tuna.tsinghua.edu.cn/simple/",
        "PYPI_CACHE_TTL": "3600",
        "PYPI_LOG_LEVEL": "INFO"
      }
    }
  }
}

Cline, Cursor, Windsurf

JSON

{
  "mcpServers": {
    "pypi-query": {
      "command": "uvx",
      "args": [
        "--from",
        "pypi-query-mcp-server",
        "pypi-query-mcp"
      ],
      "env": {
        "PYPI_INDEX_URL": "https://pypi.org/simple/"
      }
    }
  }
}

PyPI Query MCP Server

The dependency question gets answered before the install, not by the install failing.

What it is

What you get

Requirements

Setup effort

Clearing a package for the Python version you are actually running

Seeing what a new dependency drags in before you add it

Staging a build for a machine with no route to the internet

Choosing between two libraries that claim to do the same thing

10 tools

`check_package_python_compatibility`

`download_package`

`get_download_statistics`

`get_download_trends`

`get_package_compatible_python_versions`

`get_package_dependencies`

`get_package_info`

`get_package_versions`

`get_top_downloaded_packages`

`resolve_dependencies`

What to know first

Tools you get

Light Standing cost

Connect your client

Server setup

MCP Clients

Claude Code

Claude Desktop

Cline, Cursor, Windsurf

PyPI Query MCP Server

The dependency question gets answered before the install, not by the install failing.

What it is

What you get

Requirements

Setup effort

Clearing a package for the Python version you are actually running

Seeing what a new dependency drags in before you add it

Staging a build for a machine with no route to the internet

Choosing between two libraries that claim to do the same thing

10 tools

check_package_python_compatibility

download_package

get_download_statistics

get_download_trends

get_package_compatible_python_versions

get_package_dependencies

get_package_info

get_package_versions

get_top_downloaded_packages

resolve_dependencies

What to know first

Tools you get

Light Standing cost

Connect your client

Server setup

MCP Clients

Claude Code

Claude Desktop

Cline, Cursor, Windsurf

Same category

BundlerMCP

Package Registry Search

OSV

`check_package_python_compatibility`

`download_package`

`get_download_statistics`

`get_download_trends`

`get_package_compatible_python_versions`

`get_package_dependencies`

`get_package_info`

`get_package_versions`

`get_top_downloaded_packages`

`resolve_dependencies`