chore: add Claude Code plugin configuration

[amondnet]

Summary

Add Claude Code plugin configuration to enable this MCP server as a Claude Code plugin.

Closes #315

Changes

• Add .claude-plugin/plugin.json with plugin metadata
• Add .claude-plugin/install-binary.sh for automatic binary installation
• Plugin automatically downloads and extracts the correct binary for user's OS/architecture
• Supports Linux (x86_64, arm64, i386), macOS (x86_64, arm64), and Windows (x86_64, arm64, i386)
• Version pinned to v0.7.6

How it works

The install script:

1. Detects user's OS (Darwin/Linux/Windows) and architecture (x86_64/arm64/i386)
2. Downloads the appropriate archive (tar.gz or zip) from GitHub releases
3. Extracts the binary to the plugin directory
4. Caches the binary and only re-downloads if version changes

Installation

Users can add this plugin via a marketplace:

{
  "plugins": [
    {
      "name": "grafana",
      "description": "A Model Context Protocol (MCP) server for Grafana",
      "source": {
        "source": "github",
        "repo": "grafana/mcp-grafana"
      }
    }
  ]
}

Then install via:

/plugin install grafana@your-marketplace

The plugin will automatically download and configure the mcp-grafana binary on first use.

Platform Support

Platform	Architectures
Linux	x86_64, arm64, i386
macOS	x86_64 (Intel), arm64 (Apple Silicon)
Windows	x86_64, arm64, i386

Testing

The install script has been designed to work with Grafana's release format:

• macOS/Linux: mcp-grafana_${OS}_${ARCH}.tar.gz containing mcp-grafana binary
• Windows: mcp-grafana_${OS}_${ARCH}.zip containing mcp-grafana.exe binary

Related

• Issue: Add Claude Code Plugin / Marketplace #315
• Claude Code plugin documentation: https://docs.claude.com/en/docs/claude-code/plugins
• Sample marketplace: https://github.com/pleaseai/claude-code-plugins

[CLAassistant]

All committers have signed the CLA.

[sd2k]

Hey! thanks for contributing this. I would like to solve the hardcoded version issue before merging. I'll work on this separately since it'll require a new CI workflow to bump versions I suspect.

The other question I had is around Windows compatibility. The script does handle the Windows OS case but still relies on Cygwin/Git Bash etc, so we would need a separate script for Powershell users, which I don't really want to maintain... I'm curious if there is a nicer solution. It's not a blocker though.

[sd2k]

Nice thanks for the extra changes!

I might be missing something here but how is the mjs script being executed right now? Should we just remove the bash script and always use the JS one instead in plugin.json?

[amondnet]

For Windows support, I've implemented Option 2 (Node.js script) as an alternative:

• Full cross-platform support (macOS, Linux, Windows PowerShell)
• Since Claude Code users have Node.js available, no additional dependencies needed
• Uses only Node.js built-in APIs
• Both bash and Node.js scripts tested and working

The bash script remains the default, but the Node.js script provides a path forward for better Windows-native experience. Both scripts now:

• Dynamically fetch latest version from GitHub API
• Verify SHA256 checksums properly
• Support automatic updates

Let me know your preference on which script to use as the primary implementation!

[sd2k]

Thanks so much. I think we can use the Node script as the primary (or even only) implementation, since it's cross platform.

[amondnet]

@sd2k I've migrated the plugin to use Node.js-only installation.