npm packages
Behavior + supply chainSignals of credential theft, suspicious execution, persistence, and prompt injection. Plus known CVEs and npm-to-GitHub artifact checks.
Pre-install package security
Inspect npm packages and MCP servers before they enter your stack. Get a SAFE, REVIEW, or BLOCK verdict, with the evidence behind it.
Open source. Runs locally. No account required.
npx --yes [email protected] guard npm:[email protected]pkgxray guard npm:[email protected]NO HIGH- OR MEDIUM-RISK FINDINGS
The default policy permits promotion from quarantine.
npm:[email protected]SAFE means no high- or medium-risk indicators were found. It is not proof that a package is harmless.
A checkpoint before install
Packages and agent tools get real permissions. Add a deliberate check before you give them access.
Stage the package in an isolated directory. Normal scans read its files without installing it or running its code.
guard npm:package@versionCheck package behavior, known vulnerabilities, metadata, and provenance. Fixed rules decide the verdict.
Every finding cites its source.Proceed with SAFE, investigate REVIEW, or stop at BLOCK. Only SAFE promotes from quarantine by default.
The same policy in your CLI and CI.What’s under the lens
One local engine, with coverage that depends on what you’re inspecting.
Read the threat modelSignals of credential theft, suspicious execution, persistence, and prompt injection. Plus known CVEs and npm-to-GitHub artifact checks.
Install manifests, known CVEs, metadata, prompt injection, and hidden Unicode. General Python behavioral analysis is not implemented.
Audit packages and declared capabilities. The runtime proxy gates calls, checks results, and detects manifest drift; it does not track dataflow across calls.
Check npm and Python dependency manifests. Recheck a stored baseline to spot changes in versions and verdicts.
A clear boundary. Static analysis cannot clear a payload that only arrives at runtime. Listing MCP tools may launch a server; mcp-proxy runs it, and opt-in canary executes package code in a sandbox. Execution boundaries ↗
Fits where you already work
Start in your terminal, then put the same decisions into your team’s workflow.
A package reference, one command, a cited verdict.
Add install gates for Codex, Claude Code, Cursor, and Windsurf.
Expose audit tools to your agent and inspect server capabilities.
Check dependencies and use stable exit codes to enforce policy.
Evidence, including the limits
The July 19, 2026 npm validation recorded zero heuristic false blocks after retuning. It also sent 661 packages to review. Both numbers matter.
Read the July npm reportA historical result, not a guarantee for the current engine. Routine CI checks committed fixtures; live registry validation is separate. Review resolution time was not measured.
Results & review count ↗ Methodology ↗Alongside your existing tools
npm audit and OSV check for known vulnerabilities. pkgxray also inspects package code and capabilities, so suspicious behavior can surface before an advisory exists. Use them together.
Your first checkpoint
No global install required. Choose a command and run it in your terminal.
Node.js ≥ 18 / pkgxray 1.1.0 / MIT
npx --yes [email protected] guard npm:[email protected]Downloads the package into quarantine and inspects it. The package’s install scripts and code are not executed.