Skills/npm/mcp

mcp@10.13.9

VERIFIED

Publisher claims: "Model Context Protocol server for FerrLens: DNS, email, HTTP, TLS certificate and SEO checks" Observed in sandbox: no network, touches nothing outside the project, writes no memory.

Registry npm (MCP server)Publisher ferrlens · publishing for 28 daysInstalls 1,639Last detonated 2d ago
$claude mcp add mcp -- npx -y @ferrlens/mcp
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Coverage

Server started and answered tools/list.
Tested
MCP initialize and tools/list · every tool description, for hidden instructions · every file read, file written and host contacted by what ran
Not tested
what the tools do when called with real credentials

Before you give it your token

It will ask for
no credential variables read in the code
Where it talks to
ferrlens.com (its own)
What the honeypot saw
no credential files read · no network
What we could not test
what the tools do when called with real credentials

Reasonable to connect. No credential asked for, no third-party host named, Server started and answered tools/list.

Never paste a credential into a chat, a ticket or a report, including ours. How the guard holds it.

Is [email protected] safe to install?

KillerSkills ran it in the KillerSkills honeypot sandbox (2 scenarios) on 2026-11-12 and scored it 91/100 (Verified). It did what it claims and nothing else we could detect: no undeclared network egress, no credential reads, no persistent instruction writes. Summary: no network, touches nothing outside the project, writes no memory.

Behavior trace

Honeypot run · 26 s · 2 scenarios · 0 deviations
t+CategoryObserved action
0.0sprocessno install scripts in bundle
5.4sprocessdependency install exit 0
25sclaimed18 tools: dns_lookup, dns_propagation, reverse_dns, check_email_auth, check_blacklist, verify_email, get_http_headers, check_security_headers, get_page_meta, preview_open_graph, check_mixed_content, check_cors, search_certificates, check_seo, check_robots_txt, check_sitemap, check_links, get_share
25sprocessscript backend runs setup only
25sprocessno install scripts to re-run

Static findings

MEDIUM
File type combined with upload actiondist/tools/seo.js:22 · File type combined with upload action — agent may exfiltrate local data files…ings.', { url: publicUrl.describe('Sitemap URL, e.g. https://example.com/sitemap.xml') }, ({ url }) => lensPost('/v1/seo/sitemap', { url })); server.tool('check_links', 'Crawl a site from…Fix: Remove the call, or declare the host in frontmatter and explain in the README what is sent and why.
AST07

No other findings across 447 lines in 22 files.

Cost to the agent

Instructions loaded
≈58 tok
1 file · 22 in bundle
Tool list per prompt
≈1,919 tok
18 tools · 107 per tool
Handshake
475 ms
launch to tools/list, stdio
Undocumented tools
0
description under 20 chars · avg 114

Tokens estimated at four characters each. The tool list is re-read by the agent on every turn, so it is the number to compare between servers that do the same job: ranked across the index.

Known vulnerabilities

No advisories in OSV for @ferrlens/mcp@10.13.9 as of 2d ago. This is the package itself, not its dependencies.