Your agent installs code. Lazaretto checks it first.

// Free, no key. true = listed as malware, false = not listed,
// null = no definite answer (unchecked is never clear).
export async function isListedAsMalware(name: string, version: string) {
  const subject = encodeURIComponent(`npm:${name}@${version}`);
  const res = await fetch(`https://lazaretto.dev/v1/attestations/${subject}`);
  if (!res.ok) return null;
  const body = await res.json();
  if (body.found) {
    if (body.verdict === "malicious" || body.contradicted != null) return true;
    return body.advisory_check ? null : false; // the recheck gave no answer
  }
  const listed = body.identity_check?.listed_as_malware;
  return typeof listed === "boolean" ? listed : null;
}

// Before your agent runs npm install: only a definite "no" goes ahead.
if ((await isListedAsMalware("chalk", "5.6.1")) !== false) {
  throw new Error("Not installing: listed as malware, or not checked");
}

import requests
from urllib.parse import quote

def is_listed_as_malware(name: str, version: str) -> bool | None:
    """Free, no key. True, False, or None when there is no definite answer."""
    subject = quote(f"npm:{name}@{version}", "")  # encode "/" and "@" too
    r = requests.get(f"https://lazaretto.dev/v1/attestations/{subject}", timeout=10)
    if not r.ok:
        return None
    body = r.json()
    if body.get("found"):
        if body.get("verdict") == "malicious" or body.get("contradicted") is not None:
            return True
        return None if body.get("advisory_check") else False  # the recheck gave no answer
    listed = (body.get("identity_check") or {}).get("listed_as_malware")
    return listed if isinstance(listed, bool) else None

# Before your agent runs npm install: only a definite "no" goes ahead.
if is_listed_as_malware("chalk", "5.6.1") is not False:
    raise SystemExit("Not installing: listed as malware, or not checked")

# Read the code, not just the name: a full behavioral scan
curl -s -X POST https://lazaretto.dev/v1/scan \
  -H "X-API-Key: $LAZARETTO_API_KEY" \
  -H 'content-type: application/json' \
  -d '{"target":{"type":"npm_package","ref":"left-pad@1.3.0"},"depth":"full"}'

# Gate on risk: critical | high | medium | low | none | unknown
# unknown comes with an error verdict (HTTP 422): the scan did not finish. It is not a clear result.
# Each finding carries rule_id, category, severity, file and line.