version-guard

A Claude Code plugin that verifies and enforces use of the latest stable library and package versions using live documentation lookups.

Problem

Claude's training data has a knowledge cutoff. When recommending library versions, install commands, or dependency configurations, it may suggest outdated versions — leading to:

• Security vulnerabilities from known-vulnerable older releases
• Wasted migration effort when users install old versions and immediately need to upgrade
• Deprecated API usage from code examples targeting superseded releases
• Poor developer experience from outdated patterns and missing features

Solution

version-guard intercepts version-sensitive contexts and verifies the current stable release against live documentation via the Context7 MCP server before making any recommendation. It works across 13+ package ecosystems.

Supported Ecosystems

Ecosystem	Dependency Files
Node/npm	package.json, package-lock.json
Python/pip	requirements.txt, pyproject.toml, setup.py, Pipfile
Python/uv	pyproject.toml, uv.lock
Python/poetry	pyproject.toml, poetry.lock
Rust/cargo	Cargo.toml, Cargo.lock
Go	go.mod, go.sum
Ruby	Gemfile, Gemfile.lock, *.gemspec
Java/Maven	pom.xml
Java/Gradle	build.gradle, build.gradle.kts
.NET	*.csproj, packages.config
PHP/Composer	composer.json, composer.lock
Swift	Package.swift
Elixir	mix.exs

Installation

From a Plugin Marketplace

claude plugin install version-guard@<marketplace-name>

From Local Path

Clone the repository and install from the local directory:

git clone https://github.com/zircote/version-guard.git
claude plugin install --local /path/to/version-guard

From GitHub

claude plugin install --git https://github.com/zircote/version-guard.git

Requirements

• Claude Code CLI
• Context7 MCP server — The plugin uses Context7 for live documentation lookups. Configure it in your Claude Code MCP settings:

{
  "mcpServers": {
    "context7": {
      "command": "npx",
      "args": ["-y", "@context7/mcp"]
    }
  }
}

• Network access — Required to query Context7 and (as a fallback) web search for version info

Usage

Explicit Invocation

/version-guard

Then describe the library or dependency you need to verify. For example:

/version-guard What is the latest version of React?

Proactive Activation

The plugin activates automatically when Claude detects version-sensitive contexts:

• Recommending or selecting a library version
• Adding dependencies to a project
• Writing install commands (npm install, pip install, cargo add, etc.)
• Writing code examples with version-sensitive imports
• Responding to "what version of X should I use?" questions
• Upgrading or auditing existing dependencies

Example Output

When the plugin verifies a version, you'll see output like:

Using React v19.1.0 (verified current — training data may reference v18.x)

If a breaking change is detected:

React 19 removed legacy context API (contextType). Use createContext + useContext instead. See migration guide: https://react.dev/blog/2024/04/25/react-19-upgrade-guide

How It Works

1. Detects version-sensitive context in the conversation
2. Loads Context7 MCP tools (deferred tools, loaded on demand)
3. Resolves the library via mcp__context7__resolve-library-id
4. Queries current documentation via mcp__context7__query-docs
5. Applies the verified version to recommendations and install commands
6. Flags breaking changes and deprecated patterns when upgrading

Fallback

If Context7 cannot resolve a library, version-guard falls back to:

1. Web search for the latest release
2. GitHub releases page or package registry
3. Clearly states the source of version information

Plugin Structure

version-guard/
├── .claude-plugin/
│   └── plugin.json              # Plugin manifest
├── commands/
│   └── version-guard.md         # User-invocable /version-guard command
├── skills/
│   └── version-guard/
│       └── SKILL.md             # Proactive skill definition
├── references/
│   └── ecosystem-patterns.md    # Ecosystem detection and naming patterns
├── LICENSE
└── README.md

Configuration

No additional configuration is needed beyond the Context7 MCP server. The plugin works out of the box once installed and Context7 is available.

License

MIT License. See LICENSE for details.