Lazaretto
Deterministic pre-install verification for npm packages, AI agent skills and MCP tools. The free lockfile check matches every exactly pinned dependency against OSV and OpenSSF malicious-package advisories with no account. A paid scan adds behavioral analysis with file-and-line evidence. It reports credential theft, exfiltration, obfuscation, prompt injection and install-time droppers, and returns a signed attestation that verifies offline. No LLM runs in the scan path, so the same input yields the same verdict. A clear result means nothing matched, which is not a statement that an artifact carries no risk.
https://lazaretto.dev/Opens ChatGPT on the web or desktop and asks it to use the WebMCP tools available here.
Connect straight to this server’s public endpoint.
https://lazaretto.dev/mcpWe add this server to your workspace, then open Studio — saved access, one connection to many servers, with a history of what ran.
Last probed Sep 14, 2026 · lazaretto.dev
8tools discovered
Known Bad Lookup
Check a SHA-256 against Lazaretto's known-bad indicator set (refreshed daily from abuse.ch). Free and anonymous. A miss only means this exact hash is not in the indicator set; it is not a clean verdict on the artifact.
Check Lockfile
Check every EXACTLY-PINNED dependency in a lockfile against published malicious-package advisories (OSV/OpenSSF). Free, anonymous, one call for the whole tree. Accepts the contents of a package-lock.json, yarn.lock, or pnpm-lock.yaml. Only exact versions can be answered: a range like ^5.0.0 has no definitive answer because a compromised release usually sits between clean ones. Fail-closed: anything that could not be checked is returned in `unverified`, so an empty `malicious` list is an all-clea
Scan Artifact
Deterministically analyze a package, repo, skill, or file for malicious behavior (credential theft, data exfiltration, obfuscation, prompt injection aimed at the agent, install scripts) and return a verdict (malicious, flagged, clear, error) with the exact evidence and a hash of what was scanned. Metered: present an X-API-Key holding credits. If you hold a wallet instead of an account, pay per call over x402 at POST https://lazaretto.dev/v1/scan ($0.03 USDC on Base, no signup). A free key with a
Scan Lockfile Deep
Behaviorally scan EVERY exactly-pinned dependency in a lockfile, not just their identities: reads the code of each package and reports credential theft, exfiltration, obfuscation, prompt injection and install-time droppers with file-and-line evidence. This is the paid counterpart to check_lockfile, which only matches names and versions against advisories. Metered: one credit per package that returns a verdict, nothing for one that errors. Capped at 25 packages per call. Use it before installing
Scan Mcp Server
Check an MCP server BEFORE you connect to it. Asks the server to introduce itself and list its tools, then analyzes the text it hands an agent: tool names, descriptions, parameter schemas and server instructions. Catches tool poisoning (hidden directives that point the agent at private keys or at an agent config file), parameters whose real purpose is to carry secrets or your conversation out, standing orders about ANOTHER server's tools (cross-server shadowing), and invisible-unicode payloads.
Check Mcp Tools
Check tool definitions you ALREADY HOLD, with no network call to anyone. Most MCP servers run locally over stdio and have no endpoint that can be reached, so this is the only way to check them, and your client already read their tool list at startup. Paste that JSON: a whole tools/list response, a {"tools":[...]} object, or a bare array. Analyzes the same text as scan_mcp_server and applies the same rules, so a payload cannot be caught over the wire and missed here. Detects tool poisoning (hidde
Find Attestation
Ask whether anyone has already attested an artifact, BEFORE you install it or pay to scan it. Free and anonymous. Give a package identity like "chalk@5.6.1", an MCP server endpoint URL, or a sha256 content hash. Returns the signed verdict if one exists, which you can verify offline against https://lazaretto.dev/.well-known/jwks.json, plus freshness: whether the corpus has since contradicted it and whether it was attested under an older rules version. A miss is not a verdict, it only means nobody
Verify Attestation
Verify a Lazaretto scan attestation that another agent (or a README, or a lockfile) handed you, WITHOUT re-scanning or paying. Free and anonymous. Returns whether the signature is valid and Lazaretto's, the attested claims (verdict, risk, and the subject the verdict is about), and a `contradicted` flag if a previously-clear subject is now known-bad. You MUST still confirm the artifact you are about to run matches `claims.sub` (its sha256, or its package identity).
Get your MCP into directories
A working endpoint is step one. Directory coverage is the coordinated launch across ChatGPT, Claude, Cursor, the MCP Registry, and community indexes.
Directory coverage for brandsDeterministic pre-install verification for npm packages, AI agent skills and MCP tools. The free lockfile check matches every exactly pinned dependency against OSV and OpenSSF malicious-package advisories with no account. A paid scan adds behavioral analysis with file-and-line evidence. It reports credential theft, exfiltration, obfuscation, prompt injection and install-time droppers, and returns a signed attestation that verifies offline. No LLM runs in the scan path, so the same input yields the same verdict. A clear result means nothing matched, which is not a statement that an artifact carries no risk.
Use the MCP endpoint listed on this page in your MCP client configuration. One-click install pills support Claude, Cursor, VS Code, and other hosts. Copy the remote MCP URL if your client needs a manual entry.
Operate Lazaretto? Verify ownership to take over this directory entry.
This server appears in the MCPBundles directory. Verify you operate it to take over the listing — name, description, logo, contact email, and skill content. We email a 6-digit code to a maintainer address your server publishes in /.well-known/security.txt or /.well-known/mcpbundles.json. Free, takes about a minute.
Other MCP servers in this category from the directory index
MCPBundles probed 8 tools on the live server. The tool list on this page reflects what was discovered at the last refresh — connect your client to see the full set available to your session.
No provider sign-in was required during MCPBundles' probe. Your client may still need MCPBundles credentials depending on how you connect.
MCPBundles is an independent platform built on the open Model Context Protocol standard. Not affiliated with Anthropic PBC or Claude.
The Care Quality Commission provides an API to access data related to the quality and performance of...
6 tools