pkgproof MCP server

pkgproof-mcp

An MCP server that verifies an npm package before you install it.

One tool, verifypackage. It runs eight checks against pkgproof.net covering advisories, install scripts, typosquat and combosquat names, scope, repository provenance and maintainer reputation, and answers safe, caution, block or doesnot_exist with every reason labelled as fact or heuristic against its source.

The first verification each day is free and needs no configuration at all. No account, no key, no signup. Later calls the same day cost $0.05 in USDC, paid per call over x402, and only if you configure a wallet.

Install

Nothing to install or host: your MCP client runs the server itself. Needs Node 22 or newer.

Every release from 0.1.1 on is built and signed by CI and carries an npm provenance attestation tying the tarball to the commit and workflow run that produced it. A tool that reports on other packages' provenance should be checkable the same way:

npm audit signatures

The server is also listed in the MCP Registry as net.pkgproof/pkgproof.

Free, no key

Add this to your MCP client configuration and you are done:

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

Claude Code

The repository is its own plugin marketplace, so there is no JSON to edit:

/plugin marketplace add jahija-okan/pkgproof-mcp
/plugin install pkgproof@pkgproof

The plugin runs the published package pinned to the version it was released beside, not whatever npx resolves to that day.

Claude Desktop

Releases carry a prebuilt .mcpb bundle on the releases page. Download it and open it: Desktop installs the server and holds the wallet keys in the OS secret store rather than in a plain-text configuration file.

The tool

verify_package, and nothing else. One call is one verification, so the daily allowance means the same thing here as it does over HTTP.

It answers twice over: a summary the agent reads, and the service's own JSON alongside it in structuredContent, under a declared output schema, carrying the verdict, every reason with its source, and the time the verdict was computed.

Calls run one at a time. The service allows one verification in flight per payer and refuses the second, so an agent walking a dependency list is queued here rather than failed.

Two networks

pkgproof settles on two chains, each on its own endpoint. They are not interchangeable: they take different key formats, and only one of them has a free tier.

Shortened. The full README is on GitHub.